a thesis statement appears in the

Thesis Statements

What this handout is about.

This handout describes what a thesis statement is, how thesis statements work in your writing, and how you can craft or refine one for your draft.

Introduction

Writing in college often takes the form of persuasion—convincing others that you have an interesting, logical point of view on the subject you are studying. Persuasion is a skill you practice regularly in your daily life. You persuade your roommate to clean up, your parents to let you borrow the car, your friend to vote for your favorite candidate or policy. In college, course assignments often ask you to make a persuasive case in writing. You are asked to convince your reader of your point of view. This form of persuasion, often called academic argument, follows a predictable pattern in writing. After a brief introduction of your topic, you state your point of view on the topic directly and often in one sentence. This sentence is the thesis statement, and it serves as a summary of the argument you’ll make in the rest of your paper.

What is a thesis statement?

A thesis statement:

• tells the reader how you will interpret the significance of the subject matter under discussion.
• is a road map for the paper; in other words, it tells the reader what to expect from the rest of the paper.
• directly answers the question asked of you. A thesis is an interpretation of a question or subject, not the subject itself. The subject, or topic, of an essay might be World War II or Moby Dick; a thesis must then offer a way to understand the war or the novel.
• makes a claim that others might dispute.
• is usually a single sentence near the beginning of your paper (most often, at the end of the first paragraph) that presents your argument to the reader. The rest of the paper, the body of the essay, gathers and organizes evidence that will persuade the reader of the logic of your interpretation.

If your assignment asks you to take a position or develop a claim about a subject, you may need to convey that position or claim in a thesis statement near the beginning of your draft. The assignment may not explicitly state that you need a thesis statement because your instructor may assume you will include one. When in doubt, ask your instructor if the assignment requires a thesis statement. When an assignment asks you to analyze, to interpret, to compare and contrast, to demonstrate cause and effect, or to take a stand on an issue, it is likely that you are being asked to develop a thesis and to support it persuasively. (Check out our handout on understanding assignments for more information.)

How do I create a thesis?

A thesis is the result of a lengthy thinking process. Formulating a thesis is not the first thing you do after reading an essay assignment. Before you develop an argument on any topic, you have to collect and organize evidence, look for possible relationships between known facts (such as surprising contrasts or similarities), and think about the significance of these relationships. Once you do this thinking, you will probably have a “working thesis” that presents a basic or main idea and an argument that you think you can support with evidence. Both the argument and your thesis are likely to need adjustment along the way.

Writers use all kinds of techniques to stimulate their thinking and to help them clarify relationships or comprehend the broader significance of a topic and arrive at a thesis statement. For more ideas on how to get started, see our handout on brainstorming .

How do I know if my thesis is strong?

If there’s time, run it by your instructor or make an appointment at the Writing Center to get some feedback. Even if you do not have time to get advice elsewhere, you can do some thesis evaluation of your own. When reviewing your first draft and its working thesis, ask yourself the following :

• Do I answer the question? Re-reading the question prompt after constructing a working thesis can help you fix an argument that misses the focus of the question. If the prompt isn’t phrased as a question, try to rephrase it. For example, “Discuss the effect of X on Y” can be rephrased as “What is the effect of X on Y?”
• Have I taken a position that others might challenge or oppose? If your thesis simply states facts that no one would, or even could, disagree with, it’s possible that you are simply providing a summary, rather than making an argument.
• Is my thesis statement specific enough? Thesis statements that are too vague often do not have a strong argument. If your thesis contains words like “good” or “successful,” see if you could be more specific: why is something “good”; what specifically makes something “successful”?
• Does my thesis pass the “So what?” test? If a reader’s first response is likely to  be “So what?” then you need to clarify, to forge a relationship, or to connect to a larger issue.
• Does my essay support my thesis specifically and without wandering? If your thesis and the body of your essay do not seem to go together, one of them has to change. It’s okay to change your working thesis to reflect things you have figured out in the course of writing your paper. Remember, always reassess and revise your writing as necessary.
• Does my thesis pass the “how and why?” test? If a reader’s first response is “how?” or “why?” your thesis may be too open-ended and lack guidance for the reader. See what you can add to give the reader a better take on your position right from the beginning.

Suppose you are taking a course on contemporary communication, and the instructor hands out the following essay assignment: “Discuss the impact of social media on public awareness.” Looking back at your notes, you might start with this working thesis:

Social media impacts public awareness in both positive and negative ways.

You can use the questions above to help you revise this general statement into a stronger thesis.

• Do I answer the question? You can analyze this if you rephrase “discuss the impact” as “what is the impact?” This way, you can see that you’ve answered the question only very generally with the vague “positive and negative ways.”
• Have I taken a position that others might challenge or oppose? Not likely. Only people who maintain that social media has a solely positive or solely negative impact could disagree.
• Is my thesis statement specific enough? No. What are the positive effects? What are the negative effects?
• Does my thesis pass the “how and why?” test? No. Why are they positive? How are they positive? What are their causes? Why are they negative? How are they negative? What are their causes?
• Does my thesis pass the “So what?” test? No. Why should anyone care about the positive and/or negative impact of social media?

After thinking about your answers to these questions, you decide to focus on the one impact you feel strongly about and have strong evidence for:

Because not every voice on social media is reliable, people have become much more critical consumers of information, and thus, more informed voters.

This version is a much stronger thesis! It answers the question, takes a specific position that others can challenge, and it gives a sense of why it matters.

Let’s try another. Suppose your literature professor hands out the following assignment in a class on the American novel: Write an analysis of some aspect of Mark Twain’s novel Huckleberry Finn. “This will be easy,” you think. “I loved Huckleberry Finn!” You grab a pad of paper and write:

Mark Twain’s Huckleberry Finn is a great American novel.

You begin to analyze your thesis:

• Do I answer the question? No. The prompt asks you to analyze some aspect of the novel. Your working thesis is a statement of general appreciation for the entire novel.

Think about aspects of the novel that are important to its structure or meaning—for example, the role of storytelling, the contrasting scenes between the shore and the river, or the relationships between adults and children. Now you write:

In Huckleberry Finn, Mark Twain develops a contrast between life on the river and life on the shore.

• Do I answer the question? Yes!
• Have I taken a position that others might challenge or oppose? Not really. This contrast is well-known and accepted.
• Is my thesis statement specific enough? It’s getting there–you have highlighted an important aspect of the novel for investigation. However, it’s still not clear what your analysis will reveal.
• Does my thesis pass the “how and why?” test? Not yet. Compare scenes from the book and see what you discover. Free write, make lists, jot down Huck’s actions and reactions and anything else that seems interesting.
• Does my thesis pass the “So what?” test? What’s the point of this contrast? What does it signify?”

After examining the evidence and considering your own insights, you write:

Through its contrasting river and shore scenes, Twain’s Huckleberry Finn suggests that to find the true expression of American democratic ideals, one must leave “civilized” society and go back to nature.

This final thesis statement presents an interpretation of a literary work based on an analysis of its content. Of course, for the essay itself to be successful, you must now present evidence from the novel that will convince the reader of your interpretation.

Works consulted

We consulted these works while writing this handout. This is not a comprehensive list of resources on the handout’s topic, and we encourage you to do your own research to find additional publications. Please do not use this list as a model for the format of your own reference list, as it may not match the citation style you are using. For guidance on formatting citations, please see the UNC Libraries citation tutorial . We revise these tips periodically and welcome feedback.

Anson, Chris M., and Robert A. Schwegler. 2010. The Longman Handbook for Writers and Readers , 6th ed. New York: Longman.

Lunsford, Andrea A. 2015. The St. Martin’s Handbook , 8th ed. Boston: Bedford/St Martin’s.

Ramage, John D., John C. Bean, and June Johnson. 2018. The Allyn & Bacon Guide to Writing , 8th ed. New York: Pearson.

Ruszkiewicz, John J., Christy Friend, Daniel Seward, and Maxine Hairston. 2010. The Scott, Foresman Handbook for Writers , 9th ed. Boston: Pearson Education.

You may reproduce it for non-commercial use if you use the entire handout and attribute the source: The Writing Center, University of North Carolina at Chapel Hill

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Developing a Thesis Statement

Many papers you write require developing a thesis statement. In this section you’ll learn what a thesis statement is and how to write one.

Keep in mind that not all papers require thesis statements . If in doubt, please consult your instructor for assistance.

What is a thesis statement?

A thesis statement . . .

• Makes an argumentative assertion about a topic; it states the conclusions that you have reached about your topic.
• Makes a promise to the reader about the scope, purpose, and direction of your paper.
• Is focused and specific enough to be “proven” within the boundaries of your paper.
• Is generally located near the end of the introduction ; sometimes, in a long paper, the thesis will be expressed in several sentences or in an entire paragraph.
• Identifies the relationships between the pieces of evidence that you are using to support your argument.

Not all papers require thesis statements! Ask your instructor if you’re in doubt whether you need one.

Identify a topic

Your topic is the subject about which you will write. Your assignment may suggest several ways of looking at a topic; or it may name a fairly general concept that you will explore or analyze in your paper.

Consider what your assignment asks you to do

Inform yourself about your topic, focus on one aspect of your topic, ask yourself whether your topic is worthy of your efforts, generate a topic from an assignment.

Below are some possible topics based on sample assignments.

Sample assignment 1

Analyze Spain’s neutrality in World War II.

Identified topic

Franco’s role in the diplomatic relationships between the Allies and the Axis

This topic avoids generalities such as “Spain” and “World War II,” addressing instead on Franco’s role (a specific aspect of “Spain”) and the diplomatic relations between the Allies and Axis (a specific aspect of World War II).

Sample assignment 2

Analyze one of Homer’s epic similes in the Iliad.

The relationship between the portrayal of warfare and the epic simile about Simoisius at 4.547-64.

This topic focuses on a single simile and relates it to a single aspect of the Iliad ( warfare being a major theme in that work).

Developing a Thesis Statement–Additional information

Your assignment may suggest several ways of looking at a topic, or it may name a fairly general concept that you will explore or analyze in your paper. You’ll want to read your assignment carefully, looking for key terms that you can use to focus your topic.

Sample assignment: Analyze Spain’s neutrality in World War II Key terms: analyze, Spain’s neutrality, World War II

After you’ve identified the key words in your topic, the next step is to read about them in several sources, or generate as much information as possible through an analysis of your topic. Obviously, the more material or knowledge you have, the more possibilities will be available for a strong argument. For the sample assignment above, you’ll want to look at books and articles on World War II in general, and Spain’s neutrality in particular.

As you consider your options, you must decide to focus on one aspect of your topic. This means that you cannot include everything you’ve learned about your topic, nor should you go off in several directions. If you end up covering too many different aspects of a topic, your paper will sprawl and be unconvincing in its argument, and it most likely will not fulfull the assignment requirements.

For the sample assignment above, both Spain’s neutrality and World War II are topics far too broad to explore in a paper. You may instead decide to focus on Franco’s role in the diplomatic relationships between the Allies and the Axis , which narrows down what aspects of Spain’s neutrality and World War II you want to discuss, as well as establishes a specific link between those two aspects.

Before you go too far, however, ask yourself whether your topic is worthy of your efforts. Try to avoid topics that already have too much written about them (i.e., “eating disorders and body image among adolescent women”) or that simply are not important (i.e. “why I like ice cream”). These topics may lead to a thesis that is either dry fact or a weird claim that cannot be supported. A good thesis falls somewhere between the two extremes. To arrive at this point, ask yourself what is new, interesting, contestable, or controversial about your topic.

As you work on your thesis, remember to keep the rest of your paper in mind at all times . Sometimes your thesis needs to evolve as you develop new insights, find new evidence, or take a different approach to your topic.

Derive a main point from topic

Once you have a topic, you will have to decide what the main point of your paper will be. This point, the “controlling idea,” becomes the core of your argument (thesis statement) and it is the unifying idea to which you will relate all your sub-theses. You can then turn this “controlling idea” into a purpose statement about what you intend to do in your paper.

Look for patterns in your evidence

Compose a purpose statement.

Consult the examples below for suggestions on how to look for patterns in your evidence and construct a purpose statement.

• Franco first tried to negotiate with the Axis
• Franco turned to the Allies when he couldn’t get some concessions that he wanted from the Axis

Possible conclusion:

Spain’s neutrality in WWII occurred for an entirely personal reason: Franco’s desire to preserve his own (and Spain’s) power.

Purpose statement

This paper will analyze Franco’s diplomacy during World War II to see how it contributed to Spain’s neutrality.

• The simile compares Simoisius to a tree, which is a peaceful, natural image.
• The tree in the simile is chopped down to make wheels for a chariot, which is an object used in warfare.

At first, the simile seems to take the reader away from the world of warfare, but we end up back in that world by the end.

This paper will analyze the way the simile about Simoisius at 4.547-64 moves in and out of the world of warfare.

Derive purpose statement from topic

To find out what your “controlling idea” is, you have to examine and evaluate your evidence . As you consider your evidence, you may notice patterns emerging, data repeated in more than one source, or facts that favor one view more than another. These patterns or data may then lead you to some conclusions about your topic and suggest that you can successfully argue for one idea better than another.

For instance, you might find out that Franco first tried to negotiate with the Axis, but when he couldn’t get some concessions that he wanted from them, he turned to the Allies. As you read more about Franco’s decisions, you may conclude that Spain’s neutrality in WWII occurred for an entirely personal reason: his desire to preserve his own (and Spain’s) power. Based on this conclusion, you can then write a trial thesis statement to help you decide what material belongs in your paper.

Sometimes you won’t be able to find a focus or identify your “spin” or specific argument immediately. Like some writers, you might begin with a purpose statement just to get yourself going. A purpose statement is one or more sentences that announce your topic and indicate the structure of the paper but do not state the conclusions you have drawn . Thus, you might begin with something like this:

• This paper will look at modern language to see if it reflects male dominance or female oppression.
• I plan to analyze anger and derision in offensive language to see if they represent a challenge of society’s authority.

At some point, you can turn a purpose statement into a thesis statement. As you think and write about your topic, you can restrict, clarify, and refine your argument, crafting your thesis statement to reflect your thinking.

As you work on your thesis, remember to keep the rest of your paper in mind at all times. Sometimes your thesis needs to evolve as you develop new insights, find new evidence, or take a different approach to your topic.

Compose a draft thesis statement

If you are writing a paper that will have an argumentative thesis and are having trouble getting started, the techniques in the table below may help you develop a temporary or “working” thesis statement.

Begin with a purpose statement that you will later turn into a thesis statement.

Assignment: Discuss the history of the Reform Party and explain its influence on the 1990 presidential and Congressional election.

Purpose Statement: This paper briefly sketches the history of the grassroots, conservative, Perot-led Reform Party and analyzes how it influenced the economic and social ideologies of the two mainstream parties.

Question-to-Assertion

If your assignment asks a specific question(s), turn the question(s) into an assertion and give reasons why it is true or reasons for your opinion.

Assignment : What do Aylmer and Rappaccini have to be proud of? Why aren’t they satisfied with these things? How does pride, as demonstrated in “The Birthmark” and “Rappaccini’s Daughter,” lead to unexpected problems?

Beginning thesis statement: Alymer and Rappaccinni are proud of their great knowledge; however, they are also very greedy and are driven to use their knowledge to alter some aspect of nature as a test of their ability. Evil results when they try to “play God.”

Write a sentence that summarizes the main idea of the essay you plan to write.

Main idea: The reason some toys succeed in the market is that they appeal to the consumers’ sense of the ridiculous and their basic desire to laugh at themselves.

Make a list of the ideas that you want to include; consider the ideas and try to group them.

• nature = peaceful
• war matériel = violent (competes with 1?)
• need for time and space to mourn the dead
• war is inescapable (competes with 3?)

Use a formula to arrive at a working thesis statement (you will revise this later).

• although most readers of _______ have argued that _______, closer examination shows that _______.
• _______ uses _______ and _____ to prove that ________.
• phenomenon x is a result of the combination of __________, __________, and _________.

What to keep in mind as you draft an initial thesis statement

Beginning statements obtained through the methods illustrated above can serve as a framework for planning or drafting your paper, but remember they’re not yet the specific, argumentative thesis you want for the final version of your paper. In fact, in its first stages, a thesis statement usually is ill-formed or rough and serves only as a planning tool.

As you write, you may discover evidence that does not fit your temporary or “working” thesis. Or you may reach deeper insights about your topic as you do more research, and you will find that your thesis statement has to be more complicated to match the evidence that you want to use.

You must be willing to reject or omit some evidence in order to keep your paper cohesive and your reader focused. Or you may have to revise your thesis to match the evidence and insights that you want to discuss. Read your draft carefully, noting the conclusions you have drawn and the major ideas which support or prove those conclusions. These will be the elements of your final thesis statement.

Sometimes you will not be able to identify these elements in your early drafts, but as you consider how your argument is developing and how your evidence supports your main idea, ask yourself, “ What is the main point that I want to prove/discuss? ” and “ How will I convince the reader that this is true? ” When you can answer these questions, then you can begin to refine the thesis statement.

Refine and polish the thesis statement

To get to your final thesis, you’ll need to refine your draft thesis so that it’s specific and arguable.

• Ask if your draft thesis addresses the assignment
• Question each part of your draft thesis
• Clarify vague phrases and assertions
• Investigate alternatives to your draft thesis

Consult the example below for suggestions on how to refine your draft thesis statement.

Sample Assignment

Choose an activity and define it as a symbol of American culture. Your essay should cause the reader to think critically about the society which produces and enjoys that activity.

• Ask The phenomenon of drive-in facilities is an interesting symbol of american culture, and these facilities demonstrate significant characteristics of our society.This statement does not fulfill the assignment because it does not require the reader to think critically about society.

Drive-ins are an interesting symbol of American culture because they represent Americans’ significant creativity and business ingenuity.

Among the types of drive-in facilities familiar during the twentieth century, drive-in movie theaters best represent American creativity, not merely because they were the forerunner of later drive-ins and drive-throughs, but because of their impact on our culture: they changed our relationship to the automobile, changed the way people experienced movies, and changed movie-going into a family activity.

While drive-in facilities such as those at fast-food establishments, banks, pharmacies, and dry cleaners symbolize America’s economic ingenuity, they also have affected our personal standards.

While drive-in facilities such as those at fast- food restaurants, banks, pharmacies, and dry cleaners symbolize (1) Americans’ business ingenuity, they also have contributed (2) to an increasing homogenization of our culture, (3) a willingness to depersonalize relationships with others, and (4) a tendency to sacrifice quality for convenience.

This statement is now specific and fulfills all parts of the assignment. This version, like any good thesis, is not self-evident; its points, 1-4, will have to be proven with evidence in the body of the paper. The numbers in this statement indicate the order in which the points will be presented. Depending on the length of the paper, there could be one paragraph for each numbered item or there could be blocks of paragraph for even pages for each one.

Complete the final thesis statement

The bottom line.

As you move through the process of crafting a thesis, you’ll need to remember four things:

• Context matters! Think about your course materials and lectures. Try to relate your thesis to the ideas your instructor is discussing.
• As you go through the process described in this section, always keep your assignment in mind . You will be more successful when your thesis (and paper) responds to the assignment than if it argues a semi-related idea.
• Your thesis statement should be precise, focused, and contestable ; it should predict the sub-theses or blocks of information that you will use to prove your argument.
• Make sure that you keep the rest of your paper in mind at all times. Change your thesis as your paper evolves, because you do not want your thesis to promise more than your paper actually delivers.

In the beginning, the thesis statement was a tool to help you sharpen your focus, limit material and establish the paper’s purpose. When your paper is finished, however, the thesis statement becomes a tool for your reader. It tells the reader what you have learned about your topic and what evidence led you to your conclusion. It keeps the reader on track–well able to understand and appreciate your argument.

Writing Process and Structure

This is an accordion element with a series of buttons that open and close related content panels.

Getting Started with Your Paper

Interpreting Writing Assignments from Your Courses

Generating Ideas for

Creating an Argument

Thesis vs. Purpose Statements

Architecture of Arguments

Working with Sources

Quoting and Paraphrasing Sources

Using Literary Quotations

Citing Sources in Your Paper

Drafting Your Paper

Generating Ideas for Your Paper

Introductions

Paragraphing

Developing Strategic Transitions

Conclusions

Revising Your Paper

Peer Reviews

Reverse Outlines

Revising an Argumentative Paper

Revision Strategies for Longer Projects

Finishing Your Paper

Twelve Common Errors: An Editing Checklist

How to Proofread your Paper

Writing Collaboratively

Collaborative and Group Writing

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Tips and Examples for Writing Thesis Statements

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Tips for Writing Your Thesis Statement

1. Determine what kind of paper you are writing:

• An analytical paper breaks down an issue or an idea into its component parts, evaluates the issue or idea, and presents this breakdown and evaluation to the audience.
• An expository (explanatory) paper explains something to the audience.
• An argumentative paper makes a claim about a topic and justifies this claim with specific evidence. The claim could be an opinion, a policy proposal, an evaluation, a cause-and-effect statement, or an interpretation. The goal of the argumentative paper is to convince the audience that the claim is true based on the evidence provided.

If you are writing a text that does not fall under these three categories (e.g., a narrative), a thesis statement somewhere in the first paragraph could still be helpful to your reader.

2. Your thesis statement should be specific—it should cover only what you will discuss in your paper and should be supported with specific evidence.

3. The thesis statement usually appears at the end of the first paragraph of a paper.

4. Your topic may change as you write, so you may need to revise your thesis statement to reflect exactly what you have discussed in the paper.

Thesis Statement Examples

Example of an analytical thesis statement:

The paper that follows should:

• Explain the analysis of the college admission process
• Explain the challenge facing admissions counselors

Example of an expository (explanatory) thesis statement:

• Explain how students spend their time studying, attending class, and socializing with peers

Example of an argumentative thesis statement:

• Present an argument and give evidence to support the claim that students should pursue community projects before entering college

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Thesis statement.

Definition:

The thesis is usually considered the most important sentence of your essay because it outlines the central purpose of your essay in one place. A good thesis will link the subject of an essay with a controlling idea. Consider, for example, the following thesis:

People in the past spent a great deal of effort protecting themselves from witches. Subject: people feared witches Controlling Idea: people spent a great deal of effort protecting themselves

In a short essay, a thesis statement appears at, or near, the end of the introductory paragraph of the paper so that readers know the topic of the essay before they see the writer's statement of the central purpose of the essay. This way the first paragraph helps the reader understand why the writer is writing.

A thesis should be narrow in focus in order to allow the fullest exploration of its issues as possible, and it should reflect the type of paper that follows, whether it be persuasive or informative. Narrowing the focus of the thesis may require posing questions about it to yourself before committing to a final version.

What follows is a method for writing thesis statements that many writers have found useful (we found it in Chapter 3 of The Allyn & Bacon Handbook ).

1. Decide what you are writing about:

A clear, concise thesis statement does more than outline the subject in question; it makes the reader aware of the writer's stand on the subject in question, connecting a subject with a controlling idea.

2. Think about all the elements your paper will deal with:

A thesis generally consists of a subject that contains within itself a number of smaller facts; the topic sentence of each paragraph that makes up the body of the paper should refer (in some clear way) back to the ideas contained within the thesis statement in order to keep the paper from digressing.

3. Think about the purpose and tone of your paper:

A thesis statement should contain the main point of the paper and suggest to the reader a direction that the paper will take in exploring, proving, or disproving that main point.

4. State your main point in a sentence or two:

A good writer can assert the main idea of a short, coherent essay briefly. Instead of rambling, be as straightforward as possible.

5. Revise your thesis as you develop your paper:

A final version of a thesis statement will only be available after a draft of the paper it is a part of has been completed. The focus of the paper may change and evolve over the period it is written in; necessarily, the thesis statement should be revised to reflect the alterations in the paper.

Few writers finish a paper writing about the exact topic they begin with. While you write a paper, your main point may change. As you're finishing, make sure your thesis statement has changed along with the subject and controlling ideas of your paper.

Questions, comments, and other sundry things may be sent to [email protected]

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How To Write a Thesis Statement (with Useful Steps and Tips)

How To Write A Thesis Statement? Writing a thesis statement is one of the most important parts of crafting an essay. Without it, the audience is not informed as to what the purpose of the essay is or your take on it. In this article, we are going to be looking at how to write an effective and hard-hitting thesis statement that will enable you to write an excellent essay .

How To Write A Thesis Statement

What Is A Thesis Statement?

Before we begin looking at how to write a thesis statement , it is important to fully understand what one is. In short, a thesis statement is a short statement which offers the reader information on what the essay is about, stating its main point or argument. A thesis statement should appear in both the introduction paragraph as well as the conclusion paragraph of the essay .

Now that we are fully aware as to what a thesis statement is and what it is used for, we can begin to look at how to write one.

For Assigned Subjects

If you have been asked to write an essay on a specific subject or topic, you can model your thesis statement around this. For example, if you have been given the essay question of ‘How does unemployment affect homelessness?’ you could write a thesis statement in direct reply to this, it might look something like the following…

Unemployment affects homelessness in two ways, it causes a rise in how many homeless people there are which in turn has an effect on how much money is being spent on charities such as food banks and homeless shelters.

This statement neatly sums up the main point of the essay and gives a brief look into what is going to be discussed in more depth throughout the piece of writing.

For Non-Assigned Subjects

If you have free reign over the essay topic, you must first select what you are going to write about. Once you have decided on this, you can begin crafting your thesis statement. You should remember to ensure that the thesis statement takes care of the following points:

• Show one main argument or idea
• Gives space for people to disagree.
• Shows your personal conclusion on the topic.

Now let’s presume that you have chosen the topic of whether homework is conducive to learning, you need to take into consideration the following points:

• What is the main point of the essay?
• What are your views on the topic?
• Can you find any research to back your opinion or even change it?

When you have answered these questions, you are then more easily able to come up with a good thesis statement. As with the assigned essay, it is important to answer a question with your thesis statement. So, considering we are writing an essay on the subject of homework, you could then turn that subject into a question ‘Is homework conducive to learning?’ Your thesis statement might look something like this:

More and more parents are refusing to allow their children to do homework, saying that it eats into their free time and provides no benefit to learning. It has been shown that this is not true, in a study conducted in Germany, 90% of children who completed homework passed their exams with a higher grade.

The above thesis statement is strong because it:

• Shows the author’s stance on the topic.
• Provides a clear insight to the essay purpose.
• Uses clear and concise language and does not waffle .
• Expresses one main argument.

When writing your thesis statement it is important to ensure that it actively meets the above criteria in order for it to be strong and effective.

Creating a Strong Thesis Statement

Identifying the main idea.

A key step in crafting a strong thesis statement is identifying the main idea of your essay. The main idea reflects the primary subject or topic you will be discussing. To begin, make sure to have a clear understanding of the assignment and the specific requirements. If you are having trouble pinpointing the main idea, start by asking yourself what problem or question your essay aims to solve or answer. Once you have identified the main idea, use it as the focal point for your thesis statement.

Narrowing the Focus

Another crucial element in creating a solid thesis statement is narrowing the focus. Instead of attempting to address a broad topic, focus on a smaller, more specific aspect of the subject. This will help you create a strong and concise thesis statement that effectively addresses the primary question or issue.

Consider the following steps to narrow your focus:

• Break down the main idea into smaller, related components
• Determine which aspect of the topic is most relevant to your essay
• Evaluate the scope of your research and analysis

By narrowing the focus, you provide a clear and specific direction for your essay, making it easier for both you and your reader to understand the central argument.

Taking a Stand

A strong thesis statement should not only present the main idea but also take a stand. It is important to make a clear, decisive assertion that demonstrates your perspective on the subject. This means avoiding vague or weak statements, and instead, confidently presenting a well-informed and well-reasoned argument.

To create a thesis statement that takes a strong stand, ensure that it:

• Clearly articulates your position on the topic
• Is debatable, meaning that it can be supported by evidence and allows for differing opinions
• Presents a specific and strong point of view

By incorporating these elements, you demonstrate that you are knowledgeable about the subject and have formed an educated opinion based on your research and analysis.

In summary, to craft a strong thesis statement, start by identifying the main idea, narrow the focus of your essay, and take a clear stand on the subject. These steps will help ensure that your paper is well-organized, compelling, and effectively communicates your central argument.

Testing and Refining Your Thesis Statement

Evaluating your working thesis.

It is crucial to evaluate your working thesis throughout the writing process. This allows you to determine if your thesis is focused, clear, and relevant to your research. Keep these questions in mind when evaluating your thesis:

• Does it answer the research question or address the main issue?
• Is it specific and concise?
• Does it serve as a guide for your ideas and analysis?

Revise your thesis if it does not fulfill these criteria or needs improvement.

Considering Counterarguments

A powerful thesis statement should take into account potential counterarguments. By considering negative perspectives and possible objections to your argument, you can refine your thesis and ensure its strength. Examine your thesis to see if it can withstand opposing views:

• Can you think of any counterarguments?
• Do your research and analysis support the thesis statement in light of these counterarguments?
• Can you provide plausible evidence to refute the counterarguments?

If your thesis can stand up to scrutiny and maintain its focus in spite of potential objections, it is on the right track.

Revising for Clarity and Strength

Once you have evaluated your working thesis and accounted for counterarguments, it is time to revise your thesis statement for clarity and strength. To do this, follow these steps:

• Remove any vague phrases and make your thesis statement as specific as possible.
• Ensure that your thesis does not try to cover too many ideas or provide unrelated information.
• Test your thesis against new research and perspectives that emerge throughout your writing process.

By revising your thesis statement and ensuring that it is clear, concise, and backed by relevant research and analysis, you will create a strong foundation for your paper.

Supporting Your Thesis Statement

Gathering evidence.

When working on a thesis statement, it is essential to gather relevant evidence to support your position. Evidence can include statistics, research findings, primary sources, or expert opinions. Start by reviewing available material, assessing its credibility and reliability, and choosing the most reliable and valuable sources. Organize the evidence in a logical manner to make it easy for the reader to understand and follow your argument.

Understanding Topic Sentences

A well-structured paper begins with clear and concise topic sentences. Each paragraph should begin with a topic sentence that identifies the main idea of the paragraph, and it should link back to the thesis statement. This helps maintain focus and coherence throughout the paper. For example:

• In a paper about the benefits of renewable energy, a topic sentence could be: “Solar energy is a reliable and cost-effective alternative to fossil fuels.”

Analyzing Sources and Facts

Thoroughly analyze your sources to determine their relevance, credibility, and accuracy. An effective way to do this is through the following steps:

• Check the author’s background and expertise.
• Evaluate the source’s publication date and ensure it is up-to-date.
• Determine if the source is peer-reviewed or published by a reputable organization.
• Check for biased language or exaggerated claims.

When presenting facts, remain neutral and unbiased, accurately representing the information you’ve gathered. Lastly, provide proper citations to give credit to the authors and avoid plagiarism.

Organizing Your Material

Effectively organizing your material is crucial for a well-structured and coherent paper. Make sure to:

• Create an outline to map out the flow of your argument.
• Group related pieces of evidence together, using bullet points or tables when necessary for clarity.
• Transition smoothly between paragraphs to maintain the reader’s interest and understanding.

By following these steps, your paper will effectively support your thesis statement, convincingly presenting your argument and contributing to the field of education.

Additional Tips For A Good Thesis Statement

We are now going to look at some final hints to ensure that you write the best thesis statement possible.

• Ensure that your thesis statement appears in your introduction and conclusion and does not get burying deep within the body of the essay.
• Make sure that the thesis statement does not exceed two sentences.
• Avoid making obvious statements such as ‘this is an essay about….’ or ‘the point of this paper is….’ The thesis statement should be able to convey this without using such up-front language.
• Write clearly and articulately.

In conclusion, a thesis statement is a critical element in the process of writing a research paper, essay, or dissertation. It serves to provide focus, direction, and convey the main argument of the work. The following paragraphs will explore some examples, tips, and guidelines on effective thesis statement writing.

When crafting a thesis statement, it is essential to ensure it is clear, concise, and focused. One way to create a strong thesis is to consider the scope of your research and align your statement with the overall themes and objectives of the project. Using specific, well-defined language helps to articulate your argument and demonstrate a solid understanding of the topic. Consider the following example:

Example:  “Through a comparative analysis of European and American film noir, this paper will reveal the influence of post-WWII societal anxieties on the genre’s distinctive narrative and stylistic elements.”

In this example, the thesis statement clearly states the research question, the subject matter, and the intended scope of the analysis.

Additionally, it is important to be consistent with the type of paper you are writing. For instance, if you are writing an analytical paper, your thesis statement should break down the issue and present an evaluation. However, if your paper is argumentative, your thesis should make a claim and justify your stance. Here are few examples for each type:

Analytical paper:  “Through an examination of campaign strategies, this study will explore the effectiveness of social media in modern political discourse.”

Argumentative paper:  “Despite the widespread use of social media in political discourse, it is argued that traditional media continues to be pivotal in shaping public opinion.”

Finally, to aid in the comprehension and readability of your work, consider employing formatting elements such as tables and bullet points when presenting complex information. This will help ensure your thesis statement and research paper is understandable and effective in conveying your main argument.

How To Write A Thesis Statement Infographic

Writing a good thesis statement can have a big impact on your essay. A thesis statement should include the point of view of the author , the main point of the writing and be clear and easy to understand.

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How to write a thesis statement + examples

What is a thesis statement?

Is a thesis statement a question, how do you write a good thesis statement, how do i know if my thesis statement is good, examples of thesis statements, helpful resources on how to write a thesis statement, frequently asked questions about writing a thesis statement, related articles.

A thesis statement is the main argument of your paper or thesis.

The thesis statement is one of the most important elements of any piece of academic writing . It is a brief statement of your paper’s main argument. Essentially, you are stating what you will be writing about.

You can see your thesis statement as an answer to a question. While it also contains the question, it should really give an answer to the question with new information and not just restate or reiterate it.

Your thesis statement is part of your introduction. Learn more about how to write a good thesis introduction in our introduction guide .

A thesis statement is not a question. A statement must be arguable and provable through evidence and analysis. While your thesis might stem from a research question, it should be in the form of a statement.

Tip: A thesis statement is typically 1-2 sentences. For a longer project like a thesis, the statement may be several sentences or a paragraph.

A good thesis statement needs to do the following:

• Condense the main idea of your thesis into one or two sentences.
• Answer your project’s main research question.
• Clearly state your position in relation to the topic .
• Make an argument that requires support or evidence.

Once you have written down a thesis statement, check if it fulfills the following criteria:

• Your statement needs to be provable by evidence. As an argument, a thesis statement needs to be debatable.
• Your statement needs to be precise. Do not give away too much information in the thesis statement and do not load it with unnecessary information.
• Your statement cannot say that one solution is simply right or simply wrong as a matter of fact. You should draw upon verified facts to persuade the reader of your solution, but you cannot just declare something as right or wrong.

As previously mentioned, your thesis statement should answer a question.

If the question is:

What do you think the City of New York should do to reduce traffic congestion?

A good thesis statement restates the question and answers it:

In this paper, I will argue that the City of New York should focus on providing exclusive lanes for public transport and adaptive traffic signals to reduce traffic congestion by the year 2035.

Here is another example. If the question is:

How can we end poverty?

A good thesis statement should give more than one solution to the problem in question:

In this paper, I will argue that introducing universal basic income can help reduce poverty and positively impact the way we work.

• The Writing Center of the University of North Carolina has a list of questions to ask to see if your thesis is strong .

A thesis statement is part of the introduction of your paper. It is usually found in the first or second paragraph to let the reader know your research purpose from the beginning.

In general, a thesis statement should have one or two sentences. But the length really depends on the overall length of your project. Take a look at our guide about the length of thesis statements for more insight on this topic.

Here is a list of Thesis Statement Examples that will help you understand better how to write them.

Every good essay should include a thesis statement as part of its introduction, no matter the academic level. Of course, if you are a high school student you are not expected to have the same type of thesis as a PhD student.

Here is a great YouTube tutorial showing How To Write An Essay: Thesis Statements .

Margaret H. Ordoubadian University Writing Center at MTSU

University writing center, com 5: thesis statements.

Dynamic PDF:   Thesis Statements

The  thesis statement  is perhaps the most crucial part of your essay because it presents the main idea or main argument of the piece of writing. In academic essays, your thesis statement is often located in the introductory paragraph; however, this is not always the case. Consider the rhetorical situation and assignment guidelines to determine where to best place your thesis.  

What does a thesis statement do?

• Informs the reader how to interpret the paper’s significance
• Serves as a sign post for the essay, showing where the rest of the paper is headed
• Offers a unique perspective on the topic at hand
• Makes a claim or argument about a topic or issue

Creating a Thesis Statement

Once you have brainstormed about a topic, collected evidence to support your claims, and thought about the significance of your ideas, you should decide what you are arguing about the topic at hand. After this consideration, you’ll likely find yourself with a working thesis statement that expresses your main idea. You may have to write your thesis multiple times before you feel it captures all you want to say about your argument.

Remember, your thesis statement is different from the topic itself. For example, the  topic  of your paper might be “Running” or even “Why People Should Run.” Your  thesis statement , however, will present an argument about running and explain the significance.

There are two types of thesis statements, blueprint and umbrella.

• A  blueprint thesis  lists what will be discussed in your paper (EX: Running is important because A, B, and C.). While blueprint thesis statements are sometimes appropriate, you may find them limiting, especially for longer papers.
• An  umbrella thesis  presents an overview of your argument without listing all of the individual components. An umbrella thesis allows you to express your argument in a condensed, concise way (EX: People who are interested in starting an exercise program should consider running because of the instant health benefits, both physical and mental.) While we know this paper will argue that running provides physical and mental health benefits, the writer does not have to list each one that will be discussed in the essay.

After you craft your thesis statement, ask yourself some questions about what your thesis statement accomplishes. This will help strengthen and clarify your main idea:

• Do I answer the question asked of me by this assignment?
• If this essay is argumentative, have I taken a clear position?
• Is my thesis statement specific enough?
• Does my thesis pass the “so what?” test? How is this idea related to a larger significance?

Remember,  as you continue to develop your paper, your thesis statement may evolve. While your original thesis can serve as a guide, you should feel free to change your thesis based on the research you conduct or the ideas you further develop.

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While Sandel argues that pursuing perfection through genetic engineering would decrease our sense of humility, he claims that the sense of solidarity we would lose is also important.

This thesis summarizes several points in Sandel’s argument, but it does not make a claim about how we should understand his argument. A reader who read Sandel’s argument would not also need to read an essay based on this descriptive thesis.  

Broad thesis (arguable, but difficult to support with evidence) 

Michael Sandel’s arguments about genetic engineering do not take into consideration all the relevant issues.

This is an arguable claim because it would be possible to argue against it by saying that Michael Sandel’s arguments do take all of the relevant issues into consideration. But the claim is too broad. Because the thesis does not specify which “issues” it is focused on—or why it matters if they are considered—readers won’t know what the rest of the essay will argue, and the writer won’t know what to focus on. If there is a particular issue that Sandel does not address, then a more specific version of the thesis would include that issue—hand an explanation of why it is important.  

Arguable thesis with analytical claim 

While Sandel argues persuasively that our instinct to “remake” (54) ourselves into something ever more perfect is a problem, his belief that we can always draw a line between what is medically necessary and what makes us simply “better than well” (51) is less convincing.

This is an arguable analytical claim. To argue for this claim, the essay writer will need to show how evidence from the article itself points to this interpretation. It’s also a reasonable scope for a thesis because it can be supported with evidence available in the text and is neither too broad nor too narrow.  

Arguable thesis with normative claim 

Given Sandel’s argument against genetic enhancement, we should not allow parents to decide on using Human Growth Hormone for their children.

This thesis tells us what we should do about a particular issue discussed in Sandel’s article, but it does not tell us how we should understand Sandel’s argument.  

Questions to ask about your thesis 

• Is the thesis truly arguable? Does it speak to a genuine dilemma in the source, or would most readers automatically agree with it?  
• Is the thesis too obvious? Again, would most or all readers agree with it without needing to see your argument?  
• Is the thesis complex enough to require a whole essay's worth of argument?  
• Is the thesis supportable with evidence from the text rather than with generalizations or outside research?  
• Would anyone want to read a paper in which this thesis was developed? That is, can you explain what this paper is adding to our understanding of a problem, question, or topic?
• picture_as_pdf Thesis

How to write a thesis statement

Published March 20, 2021. Updated May 1, 2022.

Thesis Statement Definition

A thesis statement is the main claim that you are making in your paper.

Overview of Thesis Statement

The thesis statement is usually one sentence and is located near the beginning of your paper, usually at the end of your introduction paragraph. It tells your readers what stance you take on an issue. Most of the time, when you are writing a paper, you will be responding to a prompt. Analyzing the prompt is essential in making sure your thesis statement actually addresses the question you are trying to answer. The thesis statement needs to directly answer this prompt in a focused and specific way. Some thesis statements also acts as a guide for your paper by telling readers the order in which premises will appear in the paper. This can help the reader be prepared for what you are going to say and to anticipate some of the ideas that you may write about.

Worried about your writing? Submit your paper for a Chegg Writing essay check , or for an Expert Check proofreading . Both can help you find and fix potential writing issues.

Steps in Writing a Strong Thesis Statement

Writing a thesis statement can feel overwhelming at first, but by following these steps, you can make the process less daunting.

Step 1: Analyze the Assignment Prompt

While it seems simple, analyzing the prompt is essential in making sure your thesis statement actually supports the question you are trying to answer. If you are given a prompt by your instructor, read it carefully several times. You may want to underline or circle key action words like “claim” or “analyze” and key terms from your class. Then, try to rewrite it in your own words. Even if it doesn’t sound perfect, putting it your own words will ensure that you really understand what it is asking.

Example assignment prompt: In a well-developed essay, explain how writers like John Locke and Jean-Jacques Rousseau, as well as Enlightenment ideas, sparked the French Revolution.

Rewritten in your own words: Write a clear, well supported essay. This essay will not only be about HOW the French Revolution started, but it will be on ideas and writings (not events), specifically those of John Locke and Jean-Jacques Rousseau. Be sure to include other ideas from the Enlightenment.

At this point you will hopefully have a basic answer to the question presented in the prompt. It is okay if you don’t know exactly how to answer it, but you should jot down a simple answer to help you begin your writing.

Step 2: Do Your Research

A strong thesis statement will be clear and specific, and it will be later supported by evidence from your research. You won’t be able to write a statement like this until you do your research.

The research will look different depending on your task. If you are writing a literary analysis essay, you may need to search the text and identify important plot events, character changes, and quotations. This research may feel a lot like brainstorming. If you are writing an argumentative essay, you may need to find articles and books in the library or in databases.

While researching your topic, keep the assignment prompt and your general answer in mind. Try to see if your research supports your initial idea or if you will need to revise your idea based on the information you find.

Step 3: Narrow Your Focus

Chances are, after you complete your research, you will have more information than you need. Now is the time to look at all of the evidence, data, and sources you collected, and determine what relates specifically to your assignment prompt and your general answer and what does not. If you have irrelevant information, put it to the side and save it in case it becomes relevant later.

Next, try to categorize the research you have into a few distinct groups. If your prompt asks you to compare and contrast, you may sort based on similarities or differences. If your prompt asks you to analyze the character development of a character in a novel, you might create your categories based on changes in that character.

Step 4: Write the “Working Thesis”

Now that you understand the prompt and have completed thorough research, draft a version of your thesis. This statement is often called a “working thesis” because you will likely revise it several times throughout the writing process. Try to be clear and specific, answer the prompt directly, and state a claim you will prove in the rest of your writing.

Revising Your Thesis Statement

After you have written the first draft of your essay, it is time to go back and make sure your thesis statement still matches what you actually wrote about. Reread your thesis statement and the topic sentence of each paragraph. Make sure that all of the topic sentences directly support the thesis and that the thesis statement encompasses the ideas you presented in your body paragraphs. If you find that they don’t perfectly align, you may need to revise your thesis statement to match what you wrote.

Now is also a good time to make sure your thesis statement uses effective language. Make sure you have used active verbs instead of passive and that your tone is professional and academic. If you have words like “very” or “extremely,” you could replace them with stronger and more specific options like “significant” or “acutely.”

Examples of Working Thesis Statements and Thesis Statements

Let’s take a look at a few examples of working thesis statements and thesis statements. For this first example, your assignment prompt asked you to discuss the impact of reading on children. After a bit of research, you may land on the following idea:

It is important for children to read often when they are in early elementary school.

This statement is a good working thesis, but it is not strong enough to be your final draft. It does make a claim, but it is vague and does not provide a roadmap for the reader. It also does not discuss the impact of reading. Why is it important for children to read? What are the benefits of children reading? A stronger thesis statement might say:

Children who read often in early elementary school develop strong vocabularies and improve their reading comprehension skills, increasing their confidence in reading increasingly complex texts.

This revised thesis is more focused, is likely based on research, and helps readers see the key ideas you will discuss in the paper.

Now imagine that your professor has asked you to write an essay on the role of language in George Orwell’s 1984. After you have read through your notes, read the novel, and brainstormed ideas, you may decide on the following working thesis:

Control of language is used as a source of power in 1984.

This working thesis is a good start for your brainstorming and your outline. From here, you would want to consider how language is used as a source of power and why it is used that way. A revised thesis might read:

In George Orwell’s 1984 , the Party manipulates citizens into total submission to the Party’s ideals through Newspeak, propaganda, and altered history.

This thesis statement provides a clear guide to writing. It uses active verbs (e.g., “the Party manipulates”) and clear details of language (e.g., Newspeak, propaganda, altered history) from the novel.

Before you turn in that paper, don’t forget to cite your sources in APA format , MLA format , or a style of your choice.

Key Takeaways

• The purpose of a thesis statement is to tell your readers what claim you will be proving in your paper.
• To write a thesis statement, first analyze your prompt or identify a topic, then do your research, and finally write a “working thesis.”
• Be sure your thesis is clear, is direct, and makes a claim that you can support throughout your paper.
• Revise your thesis after you finish your first draft, adding detail to your claim and replacing weaker vocabulary choices with stronger ones.

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Writing a Paper: Thesis Statements

Basics of thesis statements.

The thesis statement is the brief articulation of your paper's central argument and purpose. You might hear it referred to as simply a "thesis." Every scholarly paper should have a thesis statement, and strong thesis statements are concise, specific, and arguable. Concise means the thesis is short: perhaps one or two sentences for a shorter paper. Specific means the thesis deals with a narrow and focused topic, appropriate to the paper's length. Arguable means that a scholar in your field could disagree (or perhaps already has!).

Strong thesis statements address specific intellectual questions, have clear positions, and use a structure that reflects the overall structure of the paper. Read on to learn more about constructing a strong thesis statement.

Being Specific

This thesis statement has no specific argument:

Needs Improvement: In this essay, I will examine two scholarly articles to find similarities and differences.

This statement is concise, but it is neither specific nor arguable—a reader might wonder, "Which scholarly articles? What is the topic of this paper? What field is the author writing in?" Additionally, the purpose of the paper—to "examine…to find similarities and differences" is not of a scholarly level. Identifying similarities and differences is a good first step, but strong academic argument goes further, analyzing what those similarities and differences might mean or imply.

Better: In this essay, I will argue that Bowler's (2003) autocratic management style, when coupled with Smith's (2007) theory of social cognition, can reduce the expenses associated with employee turnover.

The new revision here is still concise, as well as specific and arguable.  We can see that it is specific because the writer is mentioning (a) concrete ideas and (b) exact authors.  We can also gather the field (business) and the topic (management and employee turnover). The statement is arguable because the student goes beyond merely comparing; he or she draws conclusions from that comparison ("can reduce the expenses associated with employee turnover").

Making a Unique Argument

This thesis draft repeats the language of the writing prompt without making a unique argument:

Needs Improvement: The purpose of this essay is to monitor, assess, and evaluate an educational program for its strengths and weaknesses. Then, I will provide suggestions for improvement.

You can see here that the student has simply stated the paper's assignment, without articulating specifically how he or she will address it. The student can correct this error simply by phrasing the thesis statement as a specific answer to the assignment prompt.

Better: Through a series of student interviews, I found that Kennedy High School's antibullying program was ineffective. In order to address issues of conflict between students, I argue that Kennedy High School should embrace policies outlined by the California Department of Education (2010).

Words like "ineffective" and "argue" show here that the student has clearly thought through the assignment and analyzed the material; he or she is putting forth a specific and debatable position. The concrete information ("student interviews," "antibullying") further prepares the reader for the body of the paper and demonstrates how the student has addressed the assignment prompt without just restating that language.

Creating a Debate

This thesis statement includes only obvious fact or plot summary instead of argument:

Needs Improvement: Leadership is an important quality in nurse educators.

A good strategy to determine if your thesis statement is too broad (and therefore, not arguable) is to ask yourself, "Would a scholar in my field disagree with this point?" Here, we can see easily that no scholar is likely to argue that leadership is an unimportant quality in nurse educators.  The student needs to come up with a more arguable claim, and probably a narrower one; remember that a short paper needs a more focused topic than a dissertation.

Better: Roderick's (2009) theory of participatory leadership  is particularly appropriate to nurse educators working within the emergency medicine field, where students benefit most from collegial and kinesthetic learning.

Here, the student has identified a particular type of leadership ("participatory leadership"), narrowing the topic, and has made an arguable claim (this type of leadership is "appropriate" to a specific type of nurse educator). Conceivably, a scholar in the nursing field might disagree with this approach. The student's paper can now proceed, providing specific pieces of evidence to support the arguable central claim.

Choosing the Right Words

This thesis statement uses large or scholarly-sounding words that have no real substance:

Needs Improvement: Scholars should work to seize metacognitive outcomes by harnessing discipline-based networks to empower collaborative infrastructures.

There are many words in this sentence that may be buzzwords in the student's field or key terms taken from other texts, but together they do not communicate a clear, specific meaning. Sometimes students think scholarly writing means constructing complex sentences using special language, but actually it's usually a stronger choice to write clear, simple sentences. When in doubt, remember that your ideas should be complex, not your sentence structure.

Better: Ecologists should work to educate the U.S. public on conservation methods by making use of local and national green organizations to create a widespread communication plan.

Notice in the revision that the field is now clear (ecology), and the language has been made much more field-specific ("conservation methods," "green organizations"), so the reader is able to see concretely the ideas the student is communicating.

Leaving Room for Discussion

This thesis statement is not capable of development or advancement in the paper:

Needs Improvement: There are always alternatives to illegal drug use.

This sample thesis statement makes a claim, but it is not a claim that will sustain extended discussion. This claim is the type of claim that might be appropriate for the conclusion of a paper, but in the beginning of the paper, the student is left with nowhere to go. What further points can be made? If there are "always alternatives" to the problem the student is identifying, then why bother developing a paper around that claim? Ideally, a thesis statement should be complex enough to explore over the length of the entire paper.

Better: The most effective treatment plan for methamphetamine addiction may be a combination of pharmacological and cognitive therapy, as argued by Baker (2008), Smith (2009), and Xavier (2011).

In the revised thesis, you can see the student make a specific, debatable claim that has the potential to generate several pages' worth of discussion. When drafting a thesis statement, think about the questions your thesis statement will generate: What follow-up inquiries might a reader have? In the first example, there are almost no additional questions implied, but the revised example allows for a good deal more exploration.

Thesis Mad Libs

If you are having trouble getting started, try using the models below to generate a rough model of a thesis statement! These models are intended for drafting purposes only and should not appear in your final work.

• In this essay, I argue ____, using ______ to assert _____.
• While scholars have often argued ______, I argue______, because_______.
• Through an analysis of ______, I argue ______, which is important because_______.

Words to Avoid and to Embrace

When drafting your thesis statement, avoid words like explore, investigate, learn, compile, summarize , and explain to describe the main purpose of your paper. These words imply a paper that summarizes or "reports," rather than synthesizing and analyzing.

Instead of the terms above, try words like argue, critique, question , and interrogate . These more analytical words may help you begin strongly, by articulating a specific, critical, scholarly position.

Read Kayla's blog post for tips on taking a stand in a well-crafted thesis statement.

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Frequently asked questions

Where does the thesis statement go in an essay.

The thesis statement should be placed at the end of your essay introduction .

Frequently asked questions: Writing an essay

For a stronger conclusion paragraph, avoid including:

• Important evidence or analysis that wasn’t mentioned in the main body
• Generic concluding phrases (e.g. “In conclusion…”)
• Weak statements that undermine your argument (e.g. “There are good points on both sides of this issue.”)

Your conclusion should leave the reader with a strong, decisive impression of your work.

Your essay’s conclusion should contain:

• A rephrased version of your overall thesis
• A brief review of the key points you made in the main body
• An indication of why your argument matters

The conclusion may also reflect on the broader implications of your argument, showing how your ideas could applied to other contexts or debates.

The conclusion paragraph of an essay is usually shorter than the introduction . As a rule, it shouldn’t take up more than 10–15% of the text.

An essay is a focused piece of writing that explains, argues, describes, or narrates.

In high school, you may have to write many different types of essays to develop your writing skills.

Academic essays at college level are usually argumentative : you develop a clear thesis about your topic and make a case for your position using evidence, analysis and interpretation.

The “hook” is the first sentence of your essay introduction . It should lead the reader into your essay, giving a sense of why it’s interesting.

To write a good hook, avoid overly broad statements or long, dense sentences. Try to start with something clear, concise and catchy that will spark your reader’s curiosity.

Your essay introduction should include three main things, in this order:

• An opening hook to catch the reader’s attention.
• Relevant background information that the reader needs to know.
• A thesis statement that presents your main point or argument.

The length of each part depends on the length and complexity of your essay .

Let’s say you’re writing a five-paragraph  essay about the environmental impacts of dietary choices. Here are three examples of topic sentences you could use for each of the three body paragraphs :

• Research has shown that the meat industry has severe environmental impacts.
• However, many plant-based foods are also produced in environmentally damaging ways.
• It’s important to consider not only what type of diet we eat, but where our food comes from and how it is produced.

Each of these sentences expresses one main idea – by listing them in order, we can see the overall structure of the essay at a glance. Each paragraph will expand on the topic sentence with relevant detail, evidence, and arguments.

The topic sentence usually comes at the very start of the paragraph .

However, sometimes you might start with a transition sentence to summarize what was discussed in previous paragraphs, followed by the topic sentence that expresses the focus of the current paragraph.

Topic sentences help keep your writing focused and guide the reader through your argument.

In an essay or paper , each paragraph should focus on a single idea. By stating the main idea in the topic sentence, you clarify what the paragraph is about for both yourself and your reader.

A topic sentence is a sentence that expresses the main point of a paragraph . Everything else in the paragraph should relate to the topic sentence.

The thesis statement is essential in any academic essay or research paper for two main reasons:

• It gives your writing direction and focus.
• It gives the reader a concise summary of your main point.

Without a clear thesis statement, an essay can end up rambling and unfocused, leaving your reader unsure of exactly what you want to say.

Follow these four steps to come up with a thesis statement :

• Ask a question about your topic .
• Write your initial answer.
• Develop your answer by including reasons.
• Refine your answer, adding more detail and nuance.

A thesis statement is a sentence that sums up the central point of your paper or essay . Everything else you write should relate to this key idea.

An essay isn’t just a loose collection of facts and ideas. Instead, it should be centered on an overarching argument (summarized in your thesis statement ) that every part of the essay relates to.

The way you structure your essay is crucial to presenting your argument coherently. A well-structured essay helps your reader follow the logic of your ideas and understand your overall point.

The structure of an essay is divided into an introduction that presents your topic and thesis statement , a body containing your in-depth analysis and arguments, and a conclusion wrapping up your ideas.

The structure of the body is flexible, but you should always spend some time thinking about how you can organize your essay to best serve your ideas.

The vast majority of essays written at university are some sort of argumentative essay . Almost all academic writing involves building up an argument, though other types of essay might be assigned in composition classes.

Essays can present arguments about all kinds of different topics. For example:

• In a literary analysis essay, you might make an argument for a specific interpretation of a text
• In a history essay, you might present an argument for the importance of a particular event
• In a politics essay, you might argue for the validity of a certain political theory

At high school and in composition classes at university, you’ll often be told to write a specific type of essay , but you might also just be given prompts.

Look for keywords in these prompts that suggest a certain approach: The word “explain” suggests you should write an expository essay , while the word “describe” implies a descriptive essay . An argumentative essay might be prompted with the word “assess” or “argue.”

In rhetorical analysis , a claim is something the author wants the audience to believe. A support is the evidence or appeal they use to convince the reader to believe the claim. A warrant is the (often implicit) assumption that links the support with the claim.

Logos appeals to the audience’s reason, building up logical arguments . Ethos appeals to the speaker’s status or authority, making the audience more likely to trust them. Pathos appeals to the emotions, trying to make the audience feel angry or sympathetic, for example.

Collectively, these three appeals are sometimes called the rhetorical triangle . They are central to rhetorical analysis , though a piece of rhetoric might not necessarily use all of them.

The term “text” in a rhetorical analysis essay refers to whatever object you’re analyzing. It’s frequently a piece of writing or a speech, but it doesn’t have to be. For example, you could also treat an advertisement or political cartoon as a text.

The goal of a rhetorical analysis is to explain the effect a piece of writing or oratory has on its audience, how successful it is, and the devices and appeals it uses to achieve its goals.

Unlike a standard argumentative essay , it’s less about taking a position on the arguments presented, and more about exploring how they are constructed.

You should try to follow your outline as you write your essay . However, if your ideas change or it becomes clear that your structure could be better, it’s okay to depart from your essay outline . Just make sure you know why you’re doing so.

If you have to hand in your essay outline , you may be given specific guidelines stating whether you have to use full sentences. If you’re not sure, ask your supervisor.

When writing an essay outline for yourself, the choice is yours. Some students find it helpful to write out their ideas in full sentences, while others prefer to summarize them in short phrases.

You will sometimes be asked to hand in an essay outline before you start writing your essay . Your supervisor wants to see that you have a clear idea of your structure so that writing will go smoothly.

Even when you do not have to hand it in, writing an essay outline is an important part of the writing process . It’s a good idea to write one (as informally as you like) to clarify your structure for yourself whenever you are working on an essay.

Comparisons in essays are generally structured in one of two ways:

• The alternating method, where you compare your subjects side by side according to one specific aspect at a time.
• The block method, where you cover each subject separately in its entirety.

It’s also possible to combine both methods, for example by writing a full paragraph on each of your topics and then a final paragraph contrasting the two according to a specific metric.

Your subjects might be very different or quite similar, but it’s important that there be meaningful grounds for comparison . You can probably describe many differences between a cat and a bicycle, but there isn’t really any connection between them to justify the comparison.

You’ll have to write a thesis statement explaining the central point you want to make in your essay , so be sure to know in advance what connects your subjects and makes them worth comparing.

Some essay prompts include the keywords “compare” and/or “contrast.” In these cases, an essay structured around comparing and contrasting is the appropriate response.

Comparing and contrasting is also a useful approach in all kinds of academic writing : You might compare different studies in a literature review , weigh up different arguments in an argumentative essay , or consider different theoretical approaches in a theoretical framework .

The key difference is that a narrative essay is designed to tell a complete story, while a descriptive essay is meant to convey an intense description of a particular place, object, or concept.

Narrative and descriptive essays both allow you to write more personally and creatively than other kinds of essays , and similar writing skills can apply to both.

If you’re not given a specific prompt for your descriptive essay , think about places and objects you know well, that you can think of interesting ways to describe, or that have strong personal significance for you.

The best kind of object for a descriptive essay is one specific enough that you can describe its particular features in detail—don’t choose something too vague or general.

If you’re not given much guidance on what your narrative essay should be about, consider the context and scope of the assignment. What kind of story is relevant, interesting, and possible to tell within the word count?

The best kind of story for a narrative essay is one you can use to reflect on a particular theme or lesson, or that takes a surprising turn somewhere along the way.

Don’t worry too much if your topic seems unoriginal. The point of a narrative essay is how you tell the story and the point you make with it, not the subject of the story itself.

Narrative essays are usually assigned as writing exercises at high school or in university composition classes. They may also form part of a university application.

When you are prompted to tell a story about your own life or experiences, a narrative essay is usually the right response.

The majority of the essays written at university are some sort of argumentative essay . Unless otherwise specified, you can assume that the goal of any essay you’re asked to write is argumentative: To convince the reader of your position using evidence and reasoning.

In composition classes you might be given assignments that specifically test your ability to write an argumentative essay. Look out for prompts including instructions like “argue,” “assess,” or “discuss” to see if this is the goal.

At college level, you must properly cite your sources in all essays , research papers , and other academic texts (except exams and in-class exercises).

Add a citation whenever you quote , paraphrase , or summarize information or ideas from a source. You should also give full source details in a bibliography or reference list at the end of your text.

The exact format of your citations depends on which citation style you are instructed to use. The most common styles are APA , MLA , and Chicago .

An argumentative essay tends to be a longer essay involving independent research, and aims to make an original argument about a topic. Its thesis statement makes a contentious claim that must be supported in an objective, evidence-based way.

An expository essay also aims to be objective, but it doesn’t have to make an original argument. Rather, it aims to explain something (e.g., a process or idea) in a clear, concise way. Expository essays are often shorter assignments and rely less on research.

An expository essay is a common assignment in high-school and university composition classes. It might be assigned as coursework, in class, or as part of an exam.

Sometimes you might not be told explicitly to write an expository essay. Look out for prompts containing keywords like “explain” and “define.” An expository essay is usually the right response to these prompts.

An expository essay is a broad form that varies in length according to the scope of the assignment.

Expository essays are often assigned as a writing exercise or as part of an exam, in which case a five-paragraph essay of around 800 words may be appropriate.

You’ll usually be given guidelines regarding length; if you’re not sure, ask.

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Research Paper: A step-by-step guide: 3. Thesis Statement & Outline

• 1. Getting Started
• 2. Topic Ideas
• 3. Thesis Statement & Outline
• 4. Appropriate Sources
• 5. Search Techniques
• 6. Taking Notes & Documenting Sources
• 7. Evaluating Sources
• 8. Citations & Plagiarism
• 9. Writing Your Research Paper

About Thesis Statements

Qualities of a thesis statement.

Thesis statements:

• state the subject matter and main ideas of a paper.
• appear in the first paragraph and announces what you will discuss in your paper.
• define the scope and focus of your essay, and tells your reader what to expect.  
• are not a simple factual statement.  It is an assertion that states your claims and that you can prove with evidence.
• should be the product of research and your own critical thinking.
• can be very helpful in constructing an outline for your essay; for each point you make, ask yourself whether it is relevant to the thesis.

Steps you can use to create a thesis statement

1. Start out with the main topic and focus of your essay.

youth gangs + prevention and intervention programs

2. Make a claim or argument in one sentence.  It can be helpful to start with a question which you then turn into an argument

Can prevention and intervention programs stop youth gang activities?  How?  ►►►  "Prevention and intervention programs can stop youth gang activities by giving teens something else to do."

3. Revise the sentence by using specific terms.

"Early prevention programs in schools are the most effective way to prevent youth gang involvement by giving teens good activities that offer a path to success."

4. Further revise the sentence to cover the scope of your essay and make a strong statement.

"Among various prevention and intervention efforts that have been made to deal with the rapid growth of youth gangs, early school-based prevention programs are the most effective way to prevent youth gang involvement, which they do by giving teens meaningful activities that offer pathways to achievement and success."

5. Keep your thesis statement flexible and revise it as needed. In the process of researching and writing, you may find new information or refine your understanding of the topic.

You can view this short video for more tips on how to write a clear thesis statement.

An outline is the skeleton of your essay, in which you list the arguments and subtopics in a logical order. A good outline is an important element in writing a good paper. An outline helps to target your research areas, keep you within the scope without going off-track, and it can also help to keep your argument in good order when writing the essay.  Once your outline is in good shape, it is much easier to write your paper; you've already done most of the thinking, so you just need to fill in the outline with a paragraph for each point.

To write an outline: The most common way to write an outline is the list format.  List all the major topics and subtopics with the key points that support them. Put similar topics and points together and arrange them in a logical order.    Include an introduction, a body, and a conclusion. 

A list outline should arrange the main points or arguments in a hierarchical structure indicated by Roman numerals for main ideas (I, II, III...), capital letters for subtopics (A, B, C...), Arabic numerals for details (1,2,3...), and lower-case letters for fine details if needed (a,b,c...). This helps keep things organized.  

Here is a shortened example of an outline:

Introduction: background and thesis statement

I. First topic

1. Supporting evidence 2. Supporting evidence

II. Second Topic

III. Third Topic

I. Summarize the main points of your paper II. Restate your thesis in different words III. Make a strong final statement

You can see examples of a few different kinds of outlines and get more help at the Purdue OWL .

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• Next: 4. Appropriate Sources >>
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Writing Tutorial Services

How to write a thesis statement, what is a thesis statement.

Almost all of us—even if we don’t do it consciously—look early in an essay for a one- or two-sentence condensation of the argument or analysis that is to follow. We refer to that condensation as a thesis statement.

Why Should Your Essay Contain a Thesis Statement?

• to test your ideas by distilling them into a sentence or two
• to better organize and develop your argument
• to provide your reader with a “guide” to your argument

In general, your thesis statement will accomplish these goals if you think of the thesis as the answer to the question your paper explores.

How Can You Write a Good Thesis Statement?

Here are some helpful hints to get you started. You can either scroll down or select a link to a specific topic.

How to Generate a Thesis Statement if the Topic is Assigned How to Generate a Thesis Statement if the Topic is not Assigned How to Tell a Strong Thesis Statement from a Weak One

How to Generate a Thesis Statement if the Topic is Assigned

Almost all assignments, no matter how complicated, can be reduced to a single question. Your first step, then, is to distill the assignment into a specific question. For example, if your assignment is, “Write a report to the local school board explaining the potential benefits of using computers in a fourth-grade class,” turn the request into a question like, “What are the potential benefits of using computers in a fourth-grade class?” After you’ve chosen the question your essay will answer, compose one or two complete sentences answering that question.

Q: “What are the potential benefits of using computers in a fourth-grade class?” A: “The potential benefits of using computers in a fourth-grade class are . . .”

A: “Using computers in a fourth-grade class promises to improve . . .”

The answer to the question is the thesis statement for the essay.

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How to Generate a Thesis Statement if the Topic is not Assigned

Even if your assignment doesn’t ask a specific question, your thesis statement still needs to answer a question about the issue you’d like to explore. In this situation, your job is to figure out what question you’d like to write about.

A good thesis statement will usually include the following four attributes:

• take on a subject upon which reasonable people could disagree
• deal with a subject that can be adequately treated given the nature of the assignment
• express one main idea
• assert your conclusions about a subject

Let’s see how to generate a thesis statement for a social policy paper.

Brainstorm the topic . Let’s say that your class focuses upon the problems posed by changes in the dietary habits of Americans. You find that you are interested in the amount of sugar Americans consume.

You start out with a thesis statement like this:

Sugar consumption.

This fragment isn’t a thesis statement. Instead, it simply indicates a general subject. Furthermore, your reader doesn’t know what you want to say about sugar consumption.

Narrow the topic . Your readings about the topic, however, have led you to the conclusion that elementary school children are consuming far more sugar than is healthy.

You change your thesis to look like this:

Reducing sugar consumption by elementary school children.

This fragment not only announces your subject, but it focuses on one segment of the population: elementary school children. Furthermore, it raises a subject upon which reasonable people could disagree, because while most people might agree that children consume more sugar than they used to, not everyone would agree on what should be done or who should do it. You should note that this fragment is not a thesis statement because your reader doesn’t know your conclusions on the topic.

Take a position on the topic. After reflecting on the topic a little while longer, you decide that what you really want to say about this topic is that something should be done to reduce the amount of sugar these children consume.

You revise your thesis statement to look like this:

More attention should be paid to the food and beverage choices available to elementary school children.

This statement asserts your position, but the terms more attention and food and beverage choices are vague.

Use specific language . You decide to explain what you mean about food and beverage choices , so you write:

Experts estimate that half of elementary school children consume nine times the recommended daily allowance of sugar.

This statement is specific, but it isn’t a thesis. It merely reports a statistic instead of making an assertion.

Make an assertion based on clearly stated support. You finally revise your thesis statement one more time to look like this:

Because half of all American elementary school children consume nine times the recommended daily allowance of sugar, schools should be required to replace the beverages in soda machines with healthy alternatives.

Notice how the thesis answers the question, “What should be done to reduce sugar consumption by children, and who should do it?” When you started thinking about the paper, you may not have had a specific question in mind, but as you became more involved in the topic, your ideas became more specific. Your thesis changed to reflect your new insights.

How to Tell a Strong Thesis Statement from a Weak One

1. a strong thesis statement takes some sort of stand..

Remember that your thesis needs to show your conclusions about a subject. For example, if you are writing a paper for a class on fitness, you might be asked to choose a popular weight-loss product to evaluate. Here are two thesis statements:

There are some negative and positive aspects to the Banana Herb Tea Supplement.

This is a weak thesis statement. First, it fails to take a stand. Second, the phrase negative and positive aspects is vague.

Because Banana Herb Tea Supplement promotes rapid weight loss that results in the loss of muscle and lean body mass, it poses a potential danger to customers.

This is a strong thesis because it takes a stand, and because it's specific.

2. A strong thesis statement justifies discussion.

Your thesis should indicate the point of the discussion. If your assignment is to write a paper on kinship systems, using your own family as an example, you might come up with either of these two thesis statements:

My family is an extended family.

This is a weak thesis because it merely states an observation. Your reader won’t be able to tell the point of the statement, and will probably stop reading.

While most American families would view consanguineal marriage as a threat to the nuclear family structure, many Iranian families, like my own, believe that these marriages help reinforce kinship ties in an extended family.

This is a strong thesis because it shows how your experience contradicts a widely-accepted view. A good strategy for creating a strong thesis is to show that the topic is controversial. Readers will be interested in reading the rest of the essay to see how you support your point.

3. A strong thesis statement expresses one main idea.

Readers need to be able to see that your paper has one main point. If your thesis statement expresses more than one idea, then you might confuse your readers about the subject of your paper. For example:

Companies need to exploit the marketing potential of the Internet, and Web pages can provide both advertising and customer support.

This is a weak thesis statement because the reader can’t decide whether the paper is about marketing on the Internet or Web pages. To revise the thesis, the relationship between the two ideas needs to become more clear. One way to revise the thesis would be to write:

Because the Internet is filled with tremendous marketing potential, companies should exploit this potential by using Web pages that offer both advertising and customer support.

This is a strong thesis because it shows that the two ideas are related. Hint: a great many clear and engaging thesis statements contain words like because , since , so , although , unless , and however .

4. A strong thesis statement is specific.

A thesis statement should show exactly what your paper will be about, and will help you keep your paper to a manageable topic. For example, if you're writing a seven-to-ten page paper on hunger, you might say:

World hunger has many causes and effects.

This is a weak thesis statement for two major reasons. First, world hunger can’t be discussed thoroughly in seven to ten pages. Second, many causes and effects is vague. You should be able to identify specific causes and effects. A revised thesis might look like this:

Hunger persists in Glandelinia because jobs are scarce and farming in the infertile soil is rarely profitable.

This is a strong thesis statement because it narrows the subject to a more specific and manageable topic, and it also identifies the specific causes for the existence of hunger.

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How to Write a Solid Thesis Statement

The important sentence expresses your central assertion or argument

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• Writing Research Papers
• Writing Essays
• English Grammar
• M.Ed., Education Administration, University of Georgia
• B.A., History, Armstrong State University

A thesis statement provides the foundation for your entire research paper or essay. This statement is the central assertion that you want to express in your essay. A successful thesis statement is one that is made up of one or two sentences clearly laying out your central idea and expressing an informed, reasoned answer to your research question.

Usually, the thesis statement will appear at the end of the first paragraph of your paper. There are a few different types, and the content of your thesis statement will depend upon the type of paper you’re writing.

Key Takeaways: Writing a Thesis Statement

• A thesis statement gives your reader a preview of your paper's content by laying out your central idea and expressing an informed, reasoned answer to your research question.
• Thesis statements will vary depending on the type of paper you are writing, such as an expository essay, argument paper, or analytical essay.
• Before creating a thesis statement, determine whether you are defending a stance, giving an overview of an event, object, or process, or analyzing your subject

Expository Essay Thesis Statement Examples

An expository essay "exposes" the reader to a new topic; it informs the reader with details, descriptions, or explanations of a subject. If you are writing an expository essay , your thesis statement should explain to the reader what she will learn in your essay. For example:

• The United States spends more money on its military budget than all the industrialized nations combined.
• Gun-related homicides and suicides are increasing after years of decline.
• Hate crimes have increased three years in a row, according to the FBI.
• Post-traumatic stress disorder (PTSD) increases the risk of stroke and arterial fibrillation (irregular heartbeat).

These statements provide a statement of fact about the topic (not just opinion) but leave the door open for you to elaborate with plenty of details. In an expository essay, you don't need to develop an argument or prove anything; you only need to understand your topic and present it in a logical manner. A good thesis statement in an expository essay always leaves the reader wanting more details.

Types of Thesis Statements

Before creating a thesis statement, it's important to ask a few basic questions, which will help you determine the kind of essay or paper you plan to create:

• Are you defending a stance in a controversial essay ?
• Are you simply giving an overview or describing an event, object, or process?
• Are you conducting an analysis of an event, object, or process?

In every thesis statement , you will give the reader a preview of your paper's content, but the message will differ a little depending on the essay type .

Argument Thesis Statement Examples

If you have been instructed to take a stance on one side of a controversial issue, you will need to write an argument essay . Your thesis statement should express the stance you are taking and may give the reader a preview or a hint of your evidence. The thesis of an argument essay could look something like the following:

• Self-driving cars are too dangerous and should be banned from the roadways.
• The exploration of outer space is a waste of money; instead, funds should go toward solving issues on Earth, such as poverty, hunger, global warming, and traffic congestion.
• The U.S. must crack down on illegal immigration.
• Street cameras and street-view maps have led to a total loss of privacy in the United States and elsewhere.

These thesis statements are effective because they offer opinions that can be supported by evidence. If you are writing an argument essay, you can craft your own thesis around the structure of the statements above.

Analytical Essay Thesis Statement Examples

In an analytical essay assignment, you will be expected to break down a topic, process, or object in order to observe and analyze your subject piece by piece. Examples of a thesis statement for an analytical essay include:

• The criminal justice reform bill passed by the U.S. Senate in late 2018 (" The First Step Act ") aims to reduce prison sentences that disproportionately fall on nonwhite criminal defendants.
• The rise in populism and nationalism in the U.S. and European democracies has coincided with the decline of moderate and centrist parties that have dominated since WWII.
• Later-start school days increase student success for a variety of reasons.

Because the role of the thesis statement is to state the central message of your entire paper, it is important to revisit (and maybe rewrite) your thesis statement after the paper is written. In fact, it is quite normal for your message to change as you construct your paper.

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How to Write a Strong Thesis Statement: 4 Steps + Examples

What’s Covered:

What is the purpose of a thesis statement, writing a good thesis statement: 4 steps, common pitfalls to avoid, where to get your essay edited for free.

When you set out to write an essay, there has to be some kind of point to it, right? Otherwise, your essay would just be a big jumble of word salad that makes absolutely no sense. An essay needs a central point that ties into everything else. That main point is called a thesis statement, and it’s the core of any essay or research paper.

You may hear about Master degree candidates writing a thesis, and that is an entire paper–not to be confused with the thesis statement, which is typically one sentence that contains your paper’s focus. 

Read on to learn more about thesis statements and how to write them. We’ve also included some solid examples for you to reference.

Typically the last sentence of your introductory paragraph, the thesis statement serves as the roadmap for your essay. When your reader gets to the thesis statement, they should have a clear outline of your main point, as well as the information you’ll be presenting in order to either prove or support your point. 

The thesis statement should not be confused for a topic sentence , which is the first sentence of every paragraph in your essay. If you need help writing topic sentences, numerous resources are available. Topic sentences should go along with your thesis statement, though.

Since the thesis statement is the most important sentence of your entire essay or paper, it’s imperative that you get this part right. Otherwise, your paper will not have a good flow and will seem disjointed. That’s why it’s vital not to rush through developing one. It’s a methodical process with steps that you need to follow in order to create the best thesis statement possible.

Step 1: Decide what kind of paper you’re writing

When you’re assigned an essay, there are several different types you may get. Argumentative essays are designed to get the reader to agree with you on a topic. Informative or expository essays present information to the reader. Analytical essays offer up a point and then expand on it by analyzing relevant information. Thesis statements can look and sound different based on the type of paper you’re writing. For example:

• Argumentative: The United States needs a viable third political party to decrease bipartisanship, increase options, and help reduce corruption in government.
• Informative: The Libertarian party has thrown off elections before by gaining enough support in states to get on the ballot and by taking away crucial votes from candidates.
• Analytical: An analysis of past presidential elections shows that while third party votes may have been the minority, they did affect the outcome of the elections in 2020, 2016, and beyond.

Step 2: Figure out what point you want to make

Once you know what type of paper you’re writing, you then need to figure out the point you want to make with your thesis statement, and subsequently, your paper. In other words, you need to decide to answer a question about something, such as:

• What impact did reality TV have on American society?
• How has the musical Hamilton affected perception of American history?
• Why do I want to major in [chosen major here]?

If you have an argumentative essay, then you will be writing about an opinion. To make it easier, you may want to choose an opinion that you feel passionate about so that you’re writing about something that interests you. For example, if you have an interest in preserving the environment, you may want to choose a topic that relates to that. 

If you’re writing your college essay and they ask why you want to attend that school, you may want to have a main point and back it up with information, something along the lines of:

“Attending Harvard University would benefit me both academically and professionally, as it would give me a strong knowledge base upon which to build my career, develop my network, and hopefully give me an advantage in my chosen field.”

Step 3: Determine what information you’ll use to back up your point

Once you have the point you want to make, you need to figure out how you plan to back it up throughout the rest of your essay. Without this information, it will be hard to either prove or argue the main point of your thesis statement. If you decide to write about the Hamilton example, you may decide to address any falsehoods that the writer put into the musical, such as:

“The musical Hamilton, while accurate in many ways, leaves out key parts of American history, presents a nationalist view of founding fathers, and downplays the racism of the times.”

Once you’ve written your initial working thesis statement, you’ll then need to get information to back that up. For example, the musical completely leaves out Benjamin Franklin, portrays the founding fathers in a nationalist way that is too complimentary, and shows Hamilton as a staunch abolitionist despite the fact that his family likely did own slaves. 

Step 4: Revise and refine your thesis statement before you start writing

Read through your thesis statement several times before you begin to compose your full essay. You need to make sure the statement is ironclad, since it is the foundation of the entire paper. Edit it or have a peer review it for you to make sure everything makes sense and that you feel like you can truly write a paper on the topic. Once you’ve done that, you can then begin writing your paper.

When writing a thesis statement, there are some common pitfalls you should avoid so that your paper can be as solid as possible. Make sure you always edit the thesis statement before you do anything else. You also want to ensure that the thesis statement is clear and concise. Don’t make your reader hunt for your point. Finally, put your thesis statement at the end of the first paragraph and have your introduction flow toward that statement. Your reader will expect to find your statement in its traditional spot.

If you’re having trouble getting started, or need some guidance on your essay, there are tools available that can help you. CollegeVine offers a free peer essay review tool where one of your peers can read through your essay and provide you with valuable feedback. Getting essay feedback from a peer can help you wow your instructor or college admissions officer with an impactful essay that effectively illustrates your point.

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Everything You Need to Know About Thesis Statement

Table of Contents

Persuasion is a skill that every human leverages to achieve their goals. For example, you persuade your friends to join you on some trip, your parents to purchase you an automobile, and your committee or audience to provide you approval for your research proposal.

Likewise, every scholarly task is aimed to persuade your readers or audience for certain goals. And the end goal is to incline the readers towards your perspective (facts and evidence-based). So, the act of convincing readers of your viewpoints via research work is often termed academic argument, and it follows a predetermined pattern of guidelines-based writing. After providing a comprehensive introduction to the research topic, you are supposed to state your perspective on the topic in a sentence or two, known as Thesis Statement . It summarizes the argument you will make throughout the paper.

Also, the Thesis Statement often serves as an answer to your research question. Thus, the thesis statement is a must for every research paper and scholarly work.

What is Thesis Statement?

A Thesis Statement:

• Describes how you interpret the subject matter's cause, significance, and results.
• Is a guideline for the paper. In other words, it provides an understanding of the research topic.
• Directly answers the question you are asked. The thesis is not the question itself but an interpretation of it. For example, a thesis can be about World War II, and it should also provide a way to understand the war.
• Claims that other people might disagree with.
• Is a single sentence at the beginning of your paper or near the end of the first para (where you present your argument to the reader). The body of the essay is the rest of the paper. It gathers and organizes evidence to support your argument.

A thesis statement should be concise and easily understandable. Use it as a magnet to attract your readers to keep them reading your paper till the end.

What is the purpose or the goal of the thesis statement?

The real purpose of the thesis statement is:

• To establish a gateway through which your readers can make an entrance into your research paper.
• To bring the entire research paper together to an epicenter of various arguments provided throughout the paper.

Simply put, the goal of writing a strong thesis statement is to make your research paper appear interesting enough for the readers to understand it and prove your arguments right completely.

Additionally, the goal of the thesis statement varies from the kind of research you are presenting. If your thesis provides some claims, justifications, or study, you should present an argumentative thesis statement . However, if your thesis is based on analysis, interpretation, demonstration of cause and effect, comparisons, and contrast, you should develop a persuasive thesis statement.

What is the length of an Ideal Thesis Statement?

You should write your thesis statement in 1-2 sentences. Ideally, it should not be more than 50 words in total.

Also, you should try inserting the thesis statement at the end of the topic introduction or just before the background information.

While writing your thesis statement, be mindful that a thesis statement is never meant to be factual. Your thesis statement is one of the most important elements of your thesis that will help your audience understand what you discuss throughout your paper. So, ensure that your thesis statement must appear like an arguable statement, not a factual one.

Many early researchers or young scholars choose to write factual statements as thesis statements as they are easy to prove. However, resorting to factual statements instead of arguable ones will overshadow your analytical and critical thinking skills, which readers anticipate in your paper.

How to Start a Thesis Statement?

The thesis statement is an outline of your research topic in one sentence. Therefore, you must write it in a concise and catchy style. So, here are a few quick tips that help you understand how to start a thesis statement for a research paper:

Discover Your Research Question

Once the subject matter is finalized for writing a research paper, the next requirement is to figure out the research question. While formulating your research question, make sure that it shows the gaps in the current field of study and should serve as a primary interrogation point for your research.

Figure out the answer and develop your argument

Carry out intensive research to determine the perfect answer for your research question. Your answer should further guide you to structure your entire research paper and its content flow.

For example, if you write an argumentative paper, craft your opinion and create an argument. Then, develop your claim against the topics you want to cover and justify it through various data & facts.

Establish back-up for your Answer with Evidence

The more you research, the more you will learn about the variations in the research answer that you were trying to formulate. Similarly, with various sources and newer evidence coming up, you should be able to make an answer that should stand coherently, correctly, relevant, and justified enough. The answer should enhance the reader’s understanding of your paper from beginning to end.

How to determine if my thesis statement is strong?

Make a self-evaluation of your thesis statement and check if it stands the following interrogation:

• Does it answer the question?

Re-read to understand the question prompt to ensure that your answer or the thesis statement itself doesn't skip the focus of the question. Try rephrasing it if you feel that the question prompt is not structured or appropriately discussed.

• Does my thesis statement appear like an argument (for or against)?

Suppose you have chosen to present the facts and rationality behind it in the best way possible and assume that no one would or could ever disagree with it. It indicates that you've presented a summary instead of presenting an argument. So, always pick an opinion from the topic and justify your arguments backed with various evidence.

• Is the Thesis Statement explicit and specific?

It may lack a strong argument if you have written a very general statement or vaguely crafted a thesis statement. Your audience will figure it out instantly.

Therefore, if you have used words like “good’’ or “bad,” try to put it more specifically by answering and figuring out “Why something is good”? Or ''What makes something good or bad”?

• Does it clear the “So What” test?

After reading any research paper, the prompt question that pops up from a reader's mind is, "So What?". Now, if your thesis statement urges the reader with such questions, you need to develop a strong argument or relationship that bridges your research topic to a more significant real-world problem.

• Does it go beyond the “How” and “Why” assessments?

After going through your thesis statement, if the readers come up with questions like "How" and 'Why," it indicates that your statement failed to provide the reader with the critical insights to understand your thesis statement and is too open-ended. So, you must provide your readers with the best statement explaining the introduction's real significance and the impending need for further research.

Thesis Statement Examples

Follow through with some interesting and creative thesis statements to clarify your doubts and better understand the concept.

Example 1: Social Media affects public awareness both positively and negatively

Yeah, it does answer the question. However, the answer is pretty vague and generic as it shows the effects both positively and negatively.

Not accurately. The statement can be argued only with the people having opinions either on positive or the negative aspect. Therefore, it fails to address every section of the audience.

• Is the Thesis statement specific enough?

Not exactly. This thesis statement doesn't provide any details on positive and negative impacts.

No, not at all. The thesis statement stated above provides no clarifications over how the positive or negative impacts build up or the factors that build up such impacts.

Again, No. It fails to justify why anyone should bother about the impacts, be it positive or negative.

A stronger and alternate version for the above thesis statement can be:

Since not every piece of information provided on social media is credible and reliable enough, users have become avid consumers of critical information and, therefore, more informed.

Even though the above thesis statement is lengthy, it answers every question and provides details over cause, effect, and critical aspects that readers can easily challenge.

Example 2: Analytical Thesis Statement

• Water is extremely important for human survival, but consuming contaminated water poses many health risks.
• The hibernation period is one of the most important periods in animals for healthy well-being. Still, it renders them in a state of weakness and exposed to external and environmental threats.

Example 3: Argumentative Thesis Statement

• At the end of the nineteenth century, French women lawyers experienced misogynist attacks from male lawyers when they attempted to enter the legal profession because male lawyers wanted to keep women out of judgeships.
• High levels of alcohol consumption have detrimental effects on your health, such as weight gain, heart disease, and liver complications.

Tips for writing a Strong Thesis Statement

A strong thesis statement is the foremost requirement of academic writing, and it holds greater importance when written for research papers. However, it becomes more crucial when you want your readers to get convinced of your opinions or perspective of the subject matter.

Below are some pro-tips that can help you crack the code of how to write a strong thesis statement, especially for research papers, thesis, and dissertations:

Keep it specific

Readers often get disappointed and confused when you present a weak argument based on a generic thesis statement. To develop a strong thesis statement, focus on one key aspect and develop it further.

Keep it simple and clear

The essence of your entire research paper is dependent on your thesis statement. Also, a strong thesis statement stays hinged over the clarity it provides. Therefore, don't disrupt the meaning or clarity of your research paper by using some jargonish words or complexing it by combining different concepts.

Ingrain your opinions

Your thesis statement should explicitly display your opinion or position for the subject matter under discussion. Your reader wants to understand your position in detail and the factors you will justify with evidence and facts.

Make it unique and Original

Your audience or the readers have gone through the subject matter several times in their careers. Hence, you must present your thesis statement in a unique and completely original form. Never use generic statements; grow some risk-taking capability and surprise your readers.

Keep it Concise and Coherent

Your thesis statement can be considered good only if it is concise yet informational. Don’t make it wordy in any case, and never go beyond more than 50 words.

Additionally, your research paper will discuss many aspects of a topic. Still, in the end, every single aspect should come together to form a coherent whole, addressing, explaining, and justifying the research question.

Conclusion: How to write a Thesis Statement?

A strong thesis statement is the one of the most important elements of your research paper. The thesis statement always serves as a pillar that carries the entire load of a research paper and it’s several sections.

Whether your research paper is worthy of your audience time or not, entirely hinges upon your thesis statement. A thesis statement always depicts the plan for the research but a good thesis statement reflects your opinions, viewpoints and of course the trajectory that it sets for the entire paper.

So, always try to write a good thesis statement by carefully following its structure, about which we have already discussed.

Before you go: In view of your interest in simplifying research workflows, we suggest you take a look at SciSpace . In a single portal, you can complete all your research writing tasks, including literature searches.

SciSpace provides researchers, universities, and publishers with all the tools they need. Our comprehensive research repository features more than 200 million research papers from multiple disciplines with SEO-optimized abstracts, a publicly visible profile to highlight your expertise, a specially-built collaborative text editor, 20,000+ journal templates, and more.

Hope the article has explained everything that you needed to know about the thesis statement. In case you have any questions or doubts, join our SciSpace (Formerly Typeset) community platform and put your questions there. We will make sure that you get your answers at the earliest.

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Creating an Effective Thesis Outline: A Step-by-Step Guide

Creating a thesis outline might seem like a big job, but it makes the whole writing process a lot easier. This guide will show you each step to make a good thesis outline. From understanding why you need an outline to avoiding common mistakes, this article will help you stay organized and focused. By following these steps, you can make a strong outline that will guide your research and writing.

Key Takeaways

• A thesis outline helps you organize your thoughts and makes the writing process smoother.
• Start with initial research to find key themes and questions for your thesis.
• Structure your outline logically to ensure a clear flow of ideas.
• Revise your outline regularly to make sure it stays relevant and focused.
• Avoid common pitfalls like overloading with information or ignoring feedback.

Understanding the Purpose of a Thesis Outline

Creating a thesis outline is a crucial step in the academic writing process. It serves as a roadmap for your research , helping you organize your thoughts and structure your work logically . This section will delve into the purpose of a thesis outline, its importance in academic writing , and how it guides the research process.

Preliminary Steps Before Creating a Thesis Outline

Before diving into the creation of your thesis outline, it's essential to take some preliminary steps. These steps will lay a solid foundation for your research and ensure that your outline is both comprehensive and effective.

Structuring Your Thesis Outline

Creating a well-organized thesis outline is crucial for a successful thesis. It helps you structure your thoughts and ensures a logical flow of information. Here are the key steps to structuring your thesis outline effectively :

Choosing the Right Format

Selecting the appropriate format for your thesis outline is the first step. Common formats include alphanumeric, decimal, and full-sentence outlines. Choose a format that best suits your research and writing style. This decision will guide the organization of your major sections and sub-sections.

Organizing Major Sections

Divide your thesis into major sections such as the introduction, literature review, methodology, results, discussion, and conclusion. Each section should have a clear purpose and contribute to your overall thesis argument. Use headings and subheadings to break down each section into manageable parts.

Ensuring Logical Flow

A logical flow is essential for maintaining the reader's interest and understanding. Arrange your sections and sub-sections in a way that naturally progresses from one idea to the next. This will help you build a coherent argument and make your thesis more persuasive.

By following these steps, you can create a structured and effective thesis outline that will serve as a roadmap for your research and writing process.

Developing the Introduction Section

Crafting a compelling opening.

Your introduction should grab the reader's attention right from the start. Use a hook, such as a surprising fact or a thought-provoking question, to draw them in. This section sets the stage for your entire thesis, so make it engaging and relevant.

Presenting the Research Question

Clearly state the research question your thesis aims to answer. This question will guide your entire study and keep you focused. Make sure it is specific and researchable.

Outlining the Scope and Objectives

Provide an overview of the scope of your research. Explain what you will cover and what you will not. This helps set clear boundaries for your study. Additionally, outline the main objectives you aim to achieve with your research. Setting clear objectives will help you stay on track and ensure your research is focused and relevant.

Outlining the Literature Review

Summarizing Existing Research

When outlining your literature review , start by summarizing the existing research related to your topic. This involves gathering and synthesizing information from various sources, such as books, journal articles, and online databases. A well-summarized literature review provides a comprehensive overview of what has been done in your field and highlights the key findings and methodologies used by other researchers.

Identifying Research Gaps

After summarizing the existing research, the next step is to identify the gaps in the literature. These gaps represent areas where further research is needed and can help you position your study within the broader academic context. Look for questions that have not been answered or areas that have not been explored in depth. Identifying these gaps will not only justify the need for your research but also guide your research questions and objectives.

Establishing Theoretical Frameworks

Finally, establish the theoretical frameworks that will underpin your study. This involves selecting and discussing the theories and models that are relevant to your research topic. The theoretical framework provides a foundation for your study and helps to explain the relationships between different variables. By clearly outlining the theoretical frameworks, you can ensure that your research is grounded in established knowledge and contributes to the ongoing academic discourse.

Detailing the Methodology

Selecting research methods.

Choosing the right research methods is crucial for the success of your thesis. Start by deciding whether your study will be qualitative, quantitative, or a mix of both. Qualitative methods often include interviews and observations, while quantitative methods might involve surveys and experiments. Your choice should align with your research objectives and the type of data you need to collect.

Justifying Methodological Choices

Once you have selected your methods, it's important to justify why these methods are appropriate for your study. Explain how they will help you answer your research questions and achieve your objectives. This step is vital for gaining approval from stakeholders and ensuring the success of your project.

Describing Data Collection and Analysis

Detail the process of data collection and analysis . Describe the tools and techniques you will use, such as surveys, interviews, or software for data analysis. Make sure to explain how you will ensure the reliability and validity of your data. This section should provide a clear roadmap of how you will gather and interpret your data, ensuring that your research is both credible and replicable.

Presenting Research Findings

Organizing data logically.

When presenting your research findings, it's crucial to organize your data in a logical manner. This can be done by structuring your findings around key questions, hypotheses, or the overall structure of your study. Clear organization helps your audience understand your results without confusion. Consider using tables to present quantitative data succinctly.

Highlighting Key Results

Focus on the most significant results of your research. Highlight these key findings to ensure they stand out to your readers. This not only emphasizes the importance of your work but also makes it easier for others to grasp the core contributions of your study. Remember, clarity is essential in effective communication.

Using Visual Aids Effectively

Visual aids such as charts, graphs, and tables can greatly enhance the presentation of your research findings. They provide a visual representation of your data, making complex information more accessible. Ensure that your visual aids are well-labeled and directly related to the findings you are discussing. This will help in stripping the dread from data interpretation for your audience.

Analyzing and Discussing Results

Interpreting findings.

When you interpret your findings, you need to connect your analysis to your research questions and hypotheses. This involves making sense of statistical significance and drawing meaningful conclusions. Interpreting your findings helps you understand the broader implications of your research and how it contributes to the existing body of knowledge.

Comparing with Existing Literature

To provide context for your results, compare them with similar studies mentioned in your literature review. Highlight whether your findings align with or differ from previous research. This comparison can help validate your results and show how your work fits into the larger academic conversation.

Discussing Implications

Discuss the broader implications of your findings. Consider how they impact your field of study and what they mean for future research. This section should also address any limitations of your study and suggest areas for further investigation. By doing so, you demonstrate the significance of your research and its potential to influence future work.

Concluding Your Thesis

Summarizing key points.

In the conclusion, you should summarize the key points of your research. This involves revisiting the main arguments and findings discussed in your thesis. By doing so, you provide a clear and concise overview of your work, ensuring that the reader understands the significance of your research.

Restating the Thesis Statement

Restate your thesis statement in a fresh way , reflecting on how your research has supported or challenged it. This is crucial for reinforcing the main idea of your thesis and demonstrating how your work contributes to the broader field of study. Remember, a well-restated thesis can leave a lasting impression on your readers.

Suggesting Areas for Future Research

Finally, suggest areas for future research. Identify any gaps or limitations in your study and propose how future research can address these issues. This not only highlights the importance of your work but also encourages further exploration and development in your field.

Revising and Refining the Outline

Seeking feedback.

Before finalizing your thesis outline, it's crucial to seek feedback from your advisor or peers. They can provide valuable insights and identify areas that may need improvement. Don't hesitate to ask for their opinions on the structure and content of your outline. This step ensures that your outline is clear and logical.

Making Necessary Adjustments

After receiving feedback, take the time to make necessary adjustments. This may involve reorganizing sections, adding or removing content, or clarifying certain points. A reverse outline can be particularly helpful in this stage. It involves outlining an existing draft to assess its structure and coherence. This technique allows you to see if your ideas flow logically and if any sections need further development.

Ensuring Cohesion and Coherence

Finally, ensure that your outline is cohesive and coherent. Each section should connect logically to the next, and your main points should be clearly articulated. Use a checklist to verify that your outline meets these criteria. This step is essential for creating a well-structured thesis that effectively communicates your research findings.

Common Pitfalls to Avoid

Overloading with information.

One common mistake is trying to include too much information. This can make your thesis overwhelming and difficult to follow. Focus on the most relevant data and arguments to support your thesis statement. Remember, quality over quantity is key.

Lack of Clear Focus

A thesis that lacks a clear focus can confuse readers and weaken your argument. Make sure your thesis statement is specific and that each section of your outline directly supports it. Staying focused will help you create a more compelling and coherent thesis.

Ignoring Feedback

Feedback from advisors and peers is invaluable. Ignoring it can lead to missed opportunities for improvement. Take the time to consider and incorporate constructive criticism . This will not only enhance the quality of your thesis but also help you grow as a researcher.

Writing a thesis can be tricky, and many students fall into common traps. Don't let stress and confusion hold you back. Our step-by-step Thesis Action Plan is here to guide you through every stage. Ready to make your thesis journey smoother? Visit our website to learn more and get started today!

Creating an effective thesis outline is a vital step in the thesis writing process. It helps you organize your thoughts, stay focused, and ensure that your research is thorough and well-structured. By breaking down your thesis into manageable sections, you can tackle each part with confidence and clarity. Remember, a well-crafted outline not only makes the writing process smoother but also enhances the overall quality of your thesis. Stay dedicated, seek guidance when needed, and take pride in your progress. With a solid outline, you are well on your way to producing a compelling and academically rigorous thesis.

Frequently Asked Questions

Why do i need a thesis outline.

A thesis outline helps you organize your ideas and ensures your writing is structured and focused. It breaks your project into smaller, manageable parts, making the writing process faster and less stressful.

What should I do before creating a thesis outline?

Before creating a thesis outline, conduct initial research, identify key themes and questions, and set clear objectives for your study.

How should I structure my thesis outline?

Your thesis outline should include the major sections: introduction, literature review, methodology, research findings, discussion, and conclusion. Ensure each section flows logically into the next.

What is the best way to start the introduction section?

Start your introduction with a compelling opening, present your research question, and outline the scope and objectives of your thesis.

How do I organize the literature review?

Organize your literature review by summarizing existing research, identifying research gaps, and establishing theoretical frameworks relevant to your study.

What should I include in the methodology section?

In the methodology section, describe your research methods, justify your methodological choices, and explain how you collected and analyzed your data.

How can I present my research findings effectively?

Present your research findings by organizing data logically, highlighting key results, and using visual aids like charts and graphs to make the information clear and engaging.

What should I do if I get stuck while writing my thesis?

If you get stuck, take a break, seek feedback from peers or advisors, and revisit your outline to ensure your thesis remains focused and coherent.

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• Published: 28 August 2024

Health and economic impacts of Lassa vaccination campaigns in West Africa

• David R. M. Smith   ORCID: orcid.org/0000-0002-7330-4262 1   na1 ,
• Joanne Turner   ORCID: orcid.org/0000-0002-0258-2353 2 , 3   na1 ,
• Patrick Fahr 4 ,
• Lauren A. Attfield 5 , 6 ,
• Paul R. Bessell 7 ,
• Christl A. Donnelly   ORCID: orcid.org/0000-0002-0195-2463 6 , 8 , 9 ,
• Rory Gibb 5 ,
• Kate E. Jones 5 ,
• David W. Redding 10 ,
• Danny Asogun 11 ,
• Oladele Oluwafemi Ayodeji 12 ,
• Benedict N. Azuogu 13 ,
• William A. Fischer II   ORCID: orcid.org/0000-0002-4900-098X 14 ,
• Kamji Jan 15 ,
• Adebola T. Olayinka 15 ,
• David A. Wohl 14 ,
• Andrew A. Torkelson   ORCID: orcid.org/0009-0009-4126-1374 16 ,
• Katelyn A. Dinkel   ORCID: orcid.org/0009-0003-1445-8565 16 ,
• Emily J. Nixon 2 ,
• Koen B. Pouwels   ORCID: orcid.org/0000-0001-7097-8950 1 &
• T. Déirdre Hollingsworth 17 , 18  

Nature Medicine ( 2024 ) Cite this article

Metrics details

• Epidemiology
• Health care economics
• Outcomes research
• Viral infection

Lassa fever is a zoonotic disease identified by the World Health Organization (WHO) as having pandemic potential. This study estimates the health-economic burden of Lassa fever throughout West Africa and projects impacts of a series of vaccination campaigns. We also model the emergence of ‘Lassa-X’—a hypothetical pandemic Lassa virus variant—and project impacts of achieving 100 Days Mission vaccination targets. Our model predicted 2.7 million (95% uncertainty interval: 2.1–3.4 million) Lassa virus infections annually, resulting over 10 years in 2.0 million (793,800–3.9 million) disability-adjusted life years (DALYs). The most effective vaccination strategy was a population-wide preventive campaign primarily targeting WHO-classified ‘endemic’ districts. Under conservative vaccine efficacy assumptions, this campaign averted $20.1 million ($8.2–$39.0 million) in lost DALY value and $128.2 million ($67.2–$231.9 million) in societal costs (2021 international dollars ($)). Reactive vaccination in response to local outbreaks averted just one-tenth the health-economic burden of preventive campaigns. In the event of Lassa-X emerging, spreading throughout West Africa and causing approximately 1.2 million DALYs within 2 years, 100 Days Mission vaccination averted 22% of DALYs given a vaccine 70% effective against disease and 74% of DALYs given a vaccine 70% effective against both infection and disease. These findings suggest how vaccination could alleviate Lassa fever’s burden and assist in pandemic preparedness.

Lassa fever is a viral hemorrhagic disease endemic to West Africa, where infections are common but widely undetected. Lassa fever is caused by Lassa mammarenavirus (LASV), and several lines of evidence, including detailed genomic analyses, suggest that the vast majority of human LASV infections are caused by zoonotic transmission from the Natal multimammate mouse ( Mastomys natalensis ) 1 , 2 . The virus can also spread through human-to-human contact, although this has predominantly been observed in healthcare settings with inadequate infection prevention and control practices 3 .

Most LASV infections are thought to be asymptomatic or cause only mild febrile illness 4 , but Lassa fever nonetheless has a large negative impact on population health and economies. Among patients presenting to hospital, the case–fatality ratio is estimated to be approximately 15%, and long-term sequelae, such as bilateral sensorineural hearing loss, are common in survivors of Lassa fever 5 , 6 . Monetary costs per hospitalization are estimated to be high and are often paid (partly) out of pocket by patients 7 . For example, a study from Nigeria found that the average patient’s out-of-pocket expenditure on Lassa fever treatment was approximately 480% of the monthly minimum wage in 2011 (ref. 8 ).

No licensed vaccines against Lassa fever are currently available, although several candidates are under development. A recent phase 1 randomized trial of a measles-vectored Lassa vaccine showed an acceptable safety and tolerability profile, a substantial increase in LASV-specific non-neutralizing IgG concentrations and a moderate T cell response 9 , in line with the response observed in non-human primates 10 . Several other vaccines are currently at early stages of development, with five phase 1 trials and one phase 2 trial registered by October 2022 (ref. 11 ).

Lassa fever is listed by the World Health Organization (WHO) as one of the diseases posing the greatest risk to public health due to its epidemic potential and the absence of effective countermeasures 12 . In response to such concerns, in 2022, the Group of Seven forum, the Group of Twenty forum and various international governments endorsed the 100 Days Mission, a pandemic response roadmap aiming at the delivery of vaccines within 100 d of the emergence of novel pathogens with pandemic potential 13 .

In anticipation of one or more Lassa vaccine candidates being licensed in the near future, in the present study, we estimate the current health-economic burden of Lassa fever in West Africa and project the potential impacts of different reactive and preventive vaccination campaigns. We also project potential impacts of vaccination in line with the 100 Days Mission in response to the emergence of ‘Lassa-X’, a hypothetical future variant of LASV with pandemic potential. Table 1 summarizes our main findings and their implications for public policy.

Model overview

We developed an epidemiological model projecting human Lassa fever burden over a 10-year time horizon across the 15 countries of continental West Africa (Benin, Burkina Faso, Côte d’Ivoire, The Gambia, Ghana, Guinea, Guinea-Bissau, Liberia, Mali, Mauritania, Niger, Nigeria, Senegal, Sierra Leone and Togo) and their 183 level 1 subnational administrative units. These units have different names in different countries (for example, regions in Guinea, counties in Liberia and departments in Benin) but herein are collectively referred to as ‘districts’. Due to large gaps in Lassa fever surveillance and limited case reporting throughout much of its endemic range 3 , we favored a bottom-up modeling approach, synthesizing best available ecological, epidemiological, clinical and economic data to project the cumulative health and economic burden of disease.

Our model consists of six main components (see model schematic in Extended Data Fig. 1 ). First, a previously published geospatial risk map was used to predict the risk of zoonotic LASV transmission from M. natalensis to humans (‘spillover’) at the level of 0.05° × 0.05° spatial pixels throughout West Africa 14 . Second, modeled spillover risk estimates were used as inputs in a generalized linear model (GLM) to predict human LASV seroprevalence. Third, modeled human LASV seroprevalence estimates were used as inputs in a serocatalytic model including country-level population projections to predict spillover infection incidence. Fourth, spillover infections were aggregated at the district level, and a stochastic branching process model was used to simulate onward human-to-human LASV transmission. Fifth, a computational algorithm was applied retrospectively to spillover infections and ensuing transmission chains to simulate a range of reactive and preventive vaccination campaigns and to project the number of infections averted by vaccination. (Separate model components used to simulate Lassa-X transmission and vaccination are described below.) Sixth, modeled estimates of LASV infection, and of infections averted due to vaccination or occurring in vaccinated individuals, were used as inputs in a probabilistic decision-analytic model used to project the health burden of Lassa fever and associated economic costs and the health and economic burden averted due to vaccination over 10 years.

Lassa fever burden

Our model predicts a heterogeneous distribution of zoonotic LASV infection throughout West Africa (Fig. 1 ). In the absence of vaccination, the mean annual number of LASV infections throughout the region was estimated at 2.7 million (95% uncertainty interval (UI): 2.1–3.4 million) or 27.2 million (20.9–34.0 million) over the full 10-year simulation period (Extended Data Table 1 ). Just over half of all infections occurred in Nigeria (mean, 52.9%), and the vast majority (mean, 93.7%) resulted from zoonotic spillover as opposed to human-to-human transmission, due to LASV’s low estimated basic reproduction number ( R 0 ). At the district level, annual LASV infection incidence was highest in Margibi, Liberia (1,198 (943–1,475) infections per 100,000 population), followed by Denguélé, Côte d’Ivoire (1,032 (880–1,200) per 100,000 population) and Nasarawa, Nigeria (978 (803–1,162) per 100,000 population). Over 10 years, LASV infection throughout West Africa led to an estimated 5.4 million (2.7–9.9 million) mild/moderate symptomatic cases, 237,000 (148,600–345,600) hospitalizations and 39,300 (12,900–83,300) deaths, resulting in 2.0 million (793,800–3.9 million) disability-adjusted life years (DALYs). See Supplementary Appendix E for more detailed estimates of Lassa fever burden.

Top, map showing the classification of Lassa fever endemicity for different countries and ‘districts’, as defined by the US CDC and the WHO (Supplementary Appendix C.2 ). Middle, the median annual incidence of zoonotic LASV infection per 100,000 population as estimated by our model at the level of 5-km grid cells. Bottom, the median total annual number of zoonotic LASV infections as estimated by our model at the level of 5-km grid cells.

Over 10 years, Lassa fever treatment was projected to incur $338.9 million ($206.6–$506.3 million) in government-reimbursed treatment costs and $166.9 million ($116.0–$289.3 million) in out-of-pocket medical costs, resulting in catastrophic expenditures for 232,300 (145,600–338,700) individuals and pushing 167,000 (104,700–243,600) individuals below the international poverty line (Supplementary Tables E.3 and E.4 ). Missed work due to illness totaled $1.1 billion ($380.5 million–$2.2 billion) in productivity losses, primarily due to mortality in actively employed adults. Productivity losses outranked treatment costs in driving an estimated $1.6 billion ($805.1 million–$2.8 billion) in total cumulative societal costs. Hospitalization costs, not outpatient costs, were the main driver of treatment costs, but mild to moderate disease in the community resulted in greater productivity losses than severe disease in hospital (Supplementary Fig. E.2 ). Lassa fever DALYs were valued at $287.7 million ($115.4–$562.9 million) using country-specific cost-effectiveness thresholds. Finally, an alternative measure of Lassa fever’s economic burden, the value of statistical life (VSL) lost due to Lassa fever mortality, was projected at $15.3 billion ($5.0–$32.4 billion). Uncertainty in health-economic outcomes was primarily driven by uncertainty in risks of hospitalization and death (Supplementary Fig. D.2 )

Simulating Lassa vaccination campaigns

Vaccination is introduced into the population via a series of six scenarios designed to reflect realistic assumptions about vaccine stockpile, administration and efficacy (Extended Data Table 2 ). In all six scenarios, we include reactive vaccination, in which Lassa fever outbreaks trigger the local deployment of a limited vaccine stockpile in affected districts. In scenarios 2–6, we also include preventive vaccination in the form of mass, population-wide campaigns rolled out over 3 years and focusing primarily on regions classified as Lassa fever ‘endemic’. The 15 countries included in our model are categorized as high endemic, medium endemic or low endemic according to classifications published by the US Centers for Disease Control and Prevention (CDC), and districts within high-endemic countries are further classified as endemic or non-endemic according to classifications published by the WHO (Fig. 1 and Supplementary Appendix C.2 ). Two main mechanisms of vaccine efficacy are considered: protection against infection prevents individuals from acquiring LASV infection from either M. natalensis or other humans, and protection against disease prevents vaccinated individuals who become infected from progressing to disease, thus averting outpatient consultation, hospitalization, chronic sequelae and death. In our simulations, we project impacts of a vaccine that is 70% or 90% effective only against disease or 70% or 90% effective against both infection and disease. We do not consider other potential mechanistic impacts of vaccination, such as reduced infectiousness or altered behavior among vaccinated individuals, as such factors are less relevant given low estimated rates of human-to-human LASV transmission.

Health-economic impacts of vaccination against Lassa fever

The considered vaccination scenarios varied considerably in their projected impacts, with scenario 4 leading to the greatest reductions in Lassa fever burden over 10 years (Extended Data Fig. 2 and Table 2 ). In this scenario, in addition to reactive vaccination triggered in districts experiencing local outbreaks, preventive vaccination was administered to 80% of the population in WHO-classified endemic districts as well as to 5% of the population in all other districts throughout West Africa. For a vaccine 70% effective against disease with no impact on infection, over 10 years this strategy averted a mean 456,000 (226,400–822,700) mild/moderate symptomatic cases, 19,900 (12,700–28,800) hospitalizations, 3,300 (1,100–7,000) deaths and 164,100 (66,700–317,700) DALYs. Over this period, this strategy further prevented 19,800 (12,600–28,500) and 14,200 (9,000–20,500) individuals, respectively, from experiencing catastrophic or impoverishing out-of-pocket healthcare expenditures and averted $128.2 million ($67.2–$231.9 million) in societal costs, or $1.3 billion ($436.8 million–$2.8 billion) in VSL lost.

Other vaccination scenarios used fewer doses of vaccine and, in turn, averted less of Lassa fever’s health-economic burden. Scenario 3, which limited preventive vaccination to high-endemic countries, was the scenario resulting in the second greatest health-economic benefits, including the aversion of 141,400 (57,600–273,200) DALYs and $112.8 million ($59.2–$203.8 million) in societal costs. Scenarios 2, 5 and 6 varied considerably in terms of which individuals were vaccinated but ultimately resulted in similar cumulative health-economic benefits across the region, because the overall number of doses delivered under each scenario was essentially the same. By contrast, scenario 1 included only reactive and not preventive vaccination, averting just 13,700 (5,500–26,800) DALYs and $10.3 million ($5.3–$18.8 million) in societal costs, thus having approximately one-tenth the overall health-economic benefits of scenario 4.

A vaccine effective against infection in addition to disease was found to have moderately increased impact. In scenario 4, for instance, $20.1 million ($8.2–$39.0 million) in DALY value was averted by a vaccine 70% effective only against disease, whereas $27.1 million ($11.0–$52.5 million) was averted when also 70% effective against infection (Table 2 ). By comparison, a vaccine 90% effective only against disease averted $25.8 million ($10.5–$50.1 million) in DALY value (Supplementary Table E.9 ), having similar impact to a vaccine 70% effective against both infection and disease. In the best-case scenario of a vaccine 90% effective against both infection and disease, scenario 4 averted up to 3.1 million (2.4–3.7 million) infections, 240,100 (97,500–464,900) DALYs valued at $29.5 million ($12.0–$57.2 million) and $1.9 billion ($638.5 million–$4.1 billion) in VSL lost.

Geographic variation in vaccine impact depended primarily on which districts were classified as endemic and, hence, targeted for vaccination (Extended Data Fig. 2 ). Overall impacts of vaccination were greatest in Nigeria, but impacts per 100,000 population were greatest in other endemic countries (Guinea, Liberia and Sierra Leone), because Nigeria had a larger number of individuals but a smaller share of its total population living in districts classified as endemic. In turn, approximately 16% of the total population of Nigeria and 33% of the combined population of Guinea, Liberia and Sierra Leone were vaccinated by 10 years under scenarios 3 and 4 (Fig. 2 ). Given a vaccine 70% effective only against disease, these scenarios averted 10.5% of DALYs in Nigeria, 20.3% of DALYs in Liberia, 23.6% of DALYs in Guinea and 28.1% of DALYs in Sierra Leone. For a vaccine 90% effective against infection and disease, these scenarios averted 15.3% of DALYs in Nigeria, 29.4% of DALYs in Liberia, 34.1% of DALYs in Guinea and 40.7% of DALYs in Sierra Leone.

a , Share of the total population vaccinated by 10 years in each vaccination scenario ( x axis) and aggregated across three geographic levels ( y axis). b , Share of cumulative DALYs due to Lassa fever averted over 10 years by vaccination. Impacts vary greatly depending on the vaccination scenario ( x axis), the assumed vaccine efficacy ( y axis) and the geographic location (panels).

Threshold vaccine costs

Projected economic benefits of Lassa vaccination were used to calculate the threshold vaccine cost (TVC). This can be interpreted as the maximum cost per dose at which vaccination has a benefit-to-cost ratio above 1, in the specific context of our modeled vaccination campaigns and corresponding dosage assumptions (that is, a single-dose primary series followed by a single-dose booster after 5 years, with 10% dose wastage). TVCs were similar across all five preventive campaigns (scenarios 2–6) but lower for reactive vaccination (scenario 1) (Supplementary Table E.12 ). Estimated TVCs ranged from $0.51 ($0.30–$0.80) to $21.15 ($7.28–$43.97) depending on the economic perspective considered, the vaccination campaign evaluated and the vaccine’s efficacy against infection and disease. TVCs were lowest from the perspective considering only healthcare costs and monetized DALYs (range of means, $0.51–$0.91) but more than doubled given a perspective considering all societal costs (healthcare costs and productivity losses) in addition to monetized DALYs ($1.18–$2.20) and increased by more than 20-fold when considering healthcare costs and VSL ($10.54–$21.15).

Modeling ‘Lassa-X’

In addition to our analysis of Lassa fever, we modeled the emergence of ‘Lassa-X’, a hypothetical future variant of LASV with pandemic potential due to both elevated clinical severity and increased propensity for human-to-human transmission. In this analysis, Lassa-X was assumed to emerge in humans after a single spillover event, where the probability of emergence in each district is directly proportional to the estimated share of all zoonotic LASV infections occurring in each district. We assumed that prior LASV immunity, whether natural or vaccine derived, offers no protection against Lassa-X. We conceptualized Lassa-X as having Ebola-like transmission characteristics and, under baseline assumptions, a 10-fold increase in hospitalization risk relative to Lassa fever. Lassa-X transmission parameters were quantified using Ebola case data from the 2013/2016 West Africa epidemic, resulting in simulated Lassa-X outbreaks lasting for approximately 2 years before subsiding. A range of reactive 100 Days Mission vaccination scenarios were then evaluated, considering different delays to vaccine initiation, rates of vaccine uptake and degrees of efficacy against infection and disease. Finally, as for Lassa fever, we used a probabilistic decision-analytic model to project the health and economic burden of Lassa-X and burden averted as a result of vaccination.

Projected burden of Lassa-X

Under our modeling assumptions, the emergence of Lassa-X led to explosive outbreaks throughout West Africa (Fig. 3 ), spreading to 88.3% (63.9%–94.0%) of the 183 districts included in our model (Supplementary Fig. F.1 ). In total, there were 1.7 million (230,100–4.2 million) Lassa-X infections, and Nigeria accounted for by far the greatest share of infections, followed by Niger and Ghana (Supplementary Tables G.1 and G.2 ). The projected burden of Lassa-X infection was associated with a high degree of uncertainty, driven predominantly by the highly stochastic nature of simulated outbreaks (Supplementary Fig. G.2 ).

a – c , Maps of West Africa showing, for each district: the population size ( a ), the probability of Lassa-X spillover ( b ) and the mean cumulative number of Lassa-X infections over the entire outbreak (approximately 2 years) ( c ). d , e , The second row depicts the median cumulative incidence of Lassa-X infection over the entire outbreak ( d ) and the median cumulative incidence over the entire outbreak per 100,000 population in the absence of vaccination ( e ). Interquartile ranges are indicated by error bars ( n  = 10,000). f , The total number of Lassa-X infections over time in six selected countries in one randomly selected outbreak simulation in which the initial Lassa-X spillover event occurred in Niger (the red dot highlights the initial detection of the epidemic at time 0). Lines show how a vaccine with 70% efficacy against infection and disease influences infection dynamics, where line color represents the delay to vaccine rollout, and line dashing represents the rate of vaccination (the proportion of the population vaccinated over a 1-year period). g , The mean cumulative number of deaths averted due to vaccination over the entire outbreak and across all countries, depending on vaccine efficacy (panels), the rate of vaccination ( x axis) and the delay to vaccine rollout (colors). Interquartile ranges are indicated by error bars ( n  = 10,000). yr, year.

In our baseline analysis, Lassa-X resulted in 149,700 (19,700–374,400) hospitalizations and 24,800 (2,400–76,000) deaths, causing 1.2 million (132,500–3.7 million) DALYs valued at $191.1 million ($18.4–$575.2 million). Out-of-pocket treatment costs were estimated at $118.5 million ($12.2–$317.3 million), resulting in catastrophic healthcare expenditures for 147,400 (18,500–372,500) individuals and pushing 103,100 (13,600–254,300) individuals below the poverty line. Lassa-X also resulted in $737.2 million ($56.4 million–$2.4 billion) in productivity losses to the greater economy and $10.1 billion ($625.9 million–$34.1 billion) in VSL lost. In alternative scenarios where Lassa-X infection was just as likely or one-tenth as likely to result in hospitalization as LASV infection, estimates of the health-economic burden were approximately one and two orders of magnitude lower, respectively (Supplementary Table G.4 ).

Vaccination to slow the spread of Lassa-X

Impacts of vaccination on the health-economic burden of Lassa-X depend on the delay until vaccination initiation, the rate of vaccine uptake in the population and the efficacy of vaccination against infection and/or disease (Table 3 ). In the most ambitious vaccination scenario considered, vaccine administration began 100 d after initial detection of the first hospitalized case of Lassa-X at a rate equivalent to 40% of the population per year across all countries in West Africa. Assuming a vaccine 70% effective only against disease, this vaccination scenario averted 276,600 (38,000–755,900) DALYs. However, in contrast to LASV vaccination, vaccine impact was more than three-fold greater when effective against infection as well as disease. For a vaccine 70% effective against both, this most ambitious vaccination scenario averted 1.2 million (201,300–2.7 million) infections and 916,400 (108,000–2.6 million) DALYs, representing approximately 74% of the DALY burden imposed by Lassa-X. Vaccinating at half the rate (20% of the population per year) averted approximately 55% of the DALYs imposed by Lassa-X, whereas vaccinating at a low rate (2.5% of the population per year) averted just 11% of DALYs (Supplementary Tables G.5 – G.8 ). Benefits of delivering vaccines at a higher rate outweighed benefits of initiating vaccination earlier (100 d versus 160 d from outbreak detection), which, in turn, outweighed benefits of a vaccine with greater efficacy against infection and disease (90% versus 70%).

This is, to our knowledge, the first burden of disease study for Lassa fever and the first to project impacts of Lassa vaccination campaigns on population health and economies 15 . We estimated that 2.1–3.4 million human LASV infections occur annually throughout West Africa, resulting in 15,000–35,000 hospitalizations and 1,300–8,300 deaths. These figures are consistent with recent modeling work estimating 900,000–4.4 million human LASV infections per year 14 and an annual 5,000 deaths reported elsewhere 3 , 16 . We further estimated that Lassa fever causes 2.0 million DALYs, $1.6 billion in societal costs and $15.3 billion in lost VSL over 10 years. Our modeling suggests that administering Lassa vaccines preventively to districts of Nigeria, Guinea, Liberia and Sierra Leone that are currently classified as ‘endemic’ by the WHO would avert a substantial share of the burden of disease in those areas. In our most expansive rollout scenario, in which vaccine reaches approximately 80% of individuals in endemic districts and 5% of individuals elsewhere over a 3-year period, a vaccine 70% effective against disease is projected to avert 164,000 DALYs, $128 million in societal costs and $1.3 billion in VSL lost over 10 years. This corresponds to a 10.5% reduction in Lassa fever DALYs in Nigeria given vaccination among 16.1% of the population and a 24.4% reduction in DALYs across Guinea, Liberia and Sierra Leone given vaccination among 33.3% of the population. However, for the same rollout scenario, a vaccine 90% effective against both infection and disease could avert 240,000 DALYs, $188 million in societal costs and $1.9 billion in VSL lost, corresponding to a 15.3% reduction in Lassa fever DALYs in Nigeria and a 35.3% reduction across Guinea, Liberia and Sierra Leone.

Impacts of the Lassa vaccination campaigns included in our analysis were modest in countries other than Nigeria, Guinea, Liberia and Sierra Leone. This is due primarily to these simulated campaigns reflecting a constrained global vaccine stockpile (<20 million doses annually) and, hence, limited allocation to districts not currently classified as endemic by the WHO. Although our most optimistic vaccination scenario was projected to prevent as many as 1.9 million (62%) infections in endemic-classified districts (Supplementary Fig. E.4 ), these areas cover just shy of 10% of the approximately 400 million individuals living in West Africa. However, our model predicts high Lassa fever incidence and disease burden in several ‘non-endemic’ areas. This is consistent with seroprevalence data highlighting extensive underreporting of LASV infection across the region, particularly in Ghana, Côte d’Ivoire, Burkina Faso, Mali, Togo and Benin 14 , 17 , 18 , 19 . Underreporting of Lassa fever is likely due to a combination of limited surveillance resources in affected countries, the mild and non-specific symptom presentation of most cases, seasonal fluctuations in infection incidence coincident with other febrile illnesses (malaria in particular) and stigma associated with infection, making robust estimation of Lassa fever burden a great challenge 20 . Conversely, low case numbers in some areas estimated to be suitable for transmission 21 may reflect truly limited burden, driven, in part, by significant spatiotemporal heterogeneity in LASV infection prevalence and the low dispersal rate of M. natalensis 22 .

It is important to put Lassa fever’s projected health-economic burden and impacts of vaccination in context, in particular given limited economic resources available for investment in infectious disease prevention in West Africa and, hence, opportunity costs to investing in Lassa vaccination in lieu of other interventions. In Nigeria in 2021, we estimated an annual 48 (95% UI: 19–93) Lassa fever DALYs per 100,000 population. This compares to previous estimates for various emerging, neglected and vaccine-preventable diseases, including trachoma (22 DALYs per 100,000 population in Nigeria in 2019), yellow fever (25), rabies (34), lymphatic filariasis (54), intestinal nematode infections (63), diphtheria (80) and typhoid fever (93) 23 . We further predicted mean TVCs up to $2.20 per dose for preventive campaigns when considering societal costs and monetized DALYs. A global costing analysis across 18 common vaccines estimated a per-dose cost of $2.63 in low-income countries from 2011 to 2020, including supply chain and service delivery costs 24 , suggesting that it may be feasible to achieve a maximum price per dose in line with our TVC estimates. However, real-world costs for any potential forthcoming vaccines are not yet known, and it is important to consider that vaccines currently undergoing clinical trials have distinct dosage regimens 11 and that our TVC estimates are specific to our model assumptions: a single-dose primary series with a booster dose after 5 years and 10% dose wastage. All else being equal, undiscounted TVC estimates for preventive campaigns would be roughly doubled or reduced by one-third, respectively, for a vaccine not requiring a booster dose or one requiring a two-dose primary series.

The real-world cost-effectiveness of any forthcoming Lassa vaccine will depend not only on its dosage, price and clinical efficacy, estimates of which are not yet available, but also on the alternative interventions available. Novel small-molecule antivirals and monoclonal antibodies are in various stages of development 25 , 26 and may represent promising alternatives for prevention of severe Lassa fever. Our results further highlight how the choice of perspective can lead to divergent conclusions regarding vaccine cost-effectiveness 27 . For instance, TVCs were roughly one order of magnitude greater when considering VSL instead of societal costs and monetized DALYs, up to $21.15 from $2.20 per dose. This disparity is consistent with a comparative analysis of health risk valuation, highlighting greatest TVC estimation when using VSL 28 . Although our estimates of vaccine-averted DALYs, societal costs and lost VSL may complement one another to inform priority setting and decision-making 29 , caution is needed when comparing and potentially combining distinct economic metrics (and, hence, perspectives). In particular, the value inherent to VSL may encapsulate both economic productivity and health-related quality of life, so VSL must be considered independently of productivity losses and monetized life-years. Ultimately, defining the full value of vaccination in endemic areas will require ongoing engagement and priority setting across stakeholders 30 and may benefit from considering broader macroeconomic impacts of vaccination not included in our analysis 31 . However, even if a particular vaccine is identified as a priority by local stakeholders and is predicted to be cost-effective using context-specific willingness-to-pay thresholds and an appropriate perspective, investment will be possible only if vaccination is affordable—that is, if sufficient economic resources are available to cover vaccine program costs.

One major potential benefit to present investment in Lassa vaccination is increased readiness to rapidly develop and deploy vaccines against future LASV variants with pandemic potential. The coronavirus disease 2019 (COVID-19) pandemic demonstrated that prior research on coronaviruses and genetic vaccine technologies gave researchers an important head start on COVID-19 vaccine development in early 2020 (ref. 32 ). In this context, we projected impacts of ambitious vaccination campaigns in response to the emergence of a hypothetical novel LASV variant with pandemic potential. Although it is impossible to predict whether ‘Lassa-X’ will evolve and exactly which characteristics it would have, this modeling represents a plausible scenario for its emergence and spread, totaling, on average, 1.7 million infections, 150,000 hospitalizations and 25,000 deaths over roughly 2 years, resulting in 1.2 million DALYs, $1.1 billion in societal costs and $10.1 billion in VSL lost. We estimate that a vaccine 70% effective against infection and disease, with delivery starting 100 d from the first detected case, could avert roughly one-tenth of Lassa-X’s health-economic burden assuming delivery of approximately 10 million doses per year, or up to three-quarters of its burden given 160 million doses per year. Such ambitious vaccination scenarios are in keeping with the stated goals of the 100 Days Mission 13 , representing an expansive global effort to rapidly respond to emerging pandemic threats. In contrast to LASV, vaccination against Lassa-X was more than three-fold more impactful when blocking infection in addition to disease, due to indirect vaccine protection successfully slowing its explosive outbreak dynamics.

This work has several limitations. First, our projections of Lassa fever burden build upon recent estimates of spillover risk and viral transmissibility but do not account for the potential evolution of these parameters over time, for instance, due to projected impacts of climate change 22 . Second, our model appears to overestimate the magnitude of seasonal fluctuations in incidence, potentially biasing not the total number of infections but, rather, how they are distributed through time. Although peaks in Lassa fever risk during the dry season are well observed, including five-fold greater risk estimated in Nigeria 33 , a large outbreak in Liberia during the rainy season in 2019/2020 highlights that LASV nonetheless circulates year-round 34 . Third, in assuming no LASV seroreversion among previously infected people, our model potentially underestimates the number of infections occurring annually. However, fitting the infection–hospitalization ratio to hospital case data from Nigeria limits the sensitivity of model outcomes to this assumption. Fourth, our evaluation of the economic consequences of Lassa-X is conservative, as we do not account for the exportation of cases outside of West Africa nor potential externalities of such a large epidemic, including negative impacts on tourism and trade, and the oversaturation and potential collapse of healthcare services. Fifth, because poor Lassa fever knowledge has been reported among both healthcare workers and the general population in several endemic areas 35 , 36 , increased awareness resulting from vaccination campaigns could have positive externalities not considered in our analysis, including the adoption of infection prevention behaviors and timelier care-seeking. Conversely, poor Lassa fever knowledge could limit vaccine uptake, posing challenges to reaching the vaccine coverage targets considered here.

Finally, for both LASV and Lassa-X, we do not stratify risks of infection, hospitalization or death by sex or age, and infections in each country are assumed to be representative of the general population in terms of age, sex, employment and income. Seroepidemiological data from Sierra Leone show no clear association between antibodies to LASV and age, sex or occupation 37 , and studies from hospitalized patients in Sierra Leone and Nigeria show conflicting relationships between age and mortality 3 , 38 , 39 . Prospective epidemiological cohort studies, such as the ongoing Enable program, will help to better characterize Lassa fever epidemiology—including the spectrum of illness, extent of seroreversion and risk factors for infection and disease—in turn informing future modeling, vaccine trial design and intervention investment 40 . In particular, better quantification of risk in groups thought to be at high risk of infection (for example, healthcare workers) and severe disease (for example, pregnant women) will help to inform targeted vaccination strategies, which are likely to be more cost-effective than the population-wide campaigns considered in our analysis. Nevertheless, a recent stakeholder survey highlights that the preferred vaccination strategy among Lassa fever experts in West Africa is consistent with the vaccine scenarios considered here—that is, mass, proactive campaigns immunizing a wide range of people in high-risk areas—with corresponding demand forecasts reaching up to 100 million doses 41 .

Our analysis suggests that vaccination campaigns targeting known Lassa fever hotspots will help to alleviate the large health-economic burden caused by this disease. However, expanding vaccination beyond WHO-classified ‘endemic’ districts will be necessary to prevent the large burden of disease estimated to occur in neighboring areas not currently classified as endemic. Improved surveillance is greatly needed to better characterize the epidemiology of Lassa fever across West Africa, helping to inform the design of vaccination campaigns that maximize population health by better targeting those at greatest risk of infection and severe outcomes. In the hypothetical event of a novel, highly pathogenic pandemic variant emerging and devastating the region, our modeling also suggests that the ambitious vaccination targets of the 100 Days Mission could have critical impact, helping to prevent up to three-quarters of associated health-economic burden. The probability of such a variant evolving is exceedingly difficult to predict, but investment in Lassa vaccination now could nonetheless have great additional health-economic value if facilitating a more rapid vaccine response in the event of a pandemic Lassa-related virus emerging.

Inclusion and ethics

This modeling study did not involve the collection or use of any primary individual-level patient data; thus, ethics approval was not necessary. This study included local researchers throughout the research process, including stakeholder meetings, expert feedback and manuscript revision from Lassa fever researchers in regions where Lassa fever is endemic. These researchers are included as co-authors.

Zoonotic LASV transmission

The incidence of LASV spillover was estimated by extending a previously published geospatial risk model by Basinski et al. 14 (details in Supplementary Appendix A ). In brief, this model synthesizes environmental features, M. natalensis occurrence data and LASV seroprevalence data from both rodents and humans to predict rates of zoonotic LASV infection across West Africa. Environmental features were obtained as classification rasters from the Moderate Resolution Imaging Spectroradiometer dataset, including 11 landcover features and seasonally adjusted measures of temperature, rainfall and vegetation. Occurrence data include historical captures of M. natalensis confirmed with genetic methods or skull morphology across 167 locations in 13 countries from 1977 to 2017. Rodent seropositivity data cover 13 studies testing M. natalensis for LASV across six countries from 1972 to 2014, and human seropositivity data cover 94 community-based serosurveys across five countries from 1970 to 2015.

Consistent with Basinski et al. 14 , we used a GLM to predict human seroprevalence from modeled estimates of spillover risk at the level of 0.05° × 0.05° spatial pixels. To estimate incidence rates, a Susceptible–Infected–Recovered model was used to model transitions among susceptible (seronegative), infected (seropositive) and recovered (seropositive) states. To account for change in human population size over time, this model was augmented with data on per-capita human birth and death rates for each country for each year from 1960 to 2019. Using a forward Euler model with 4-week timesteps, we estimated the number of new infections in each timestep that reproduced modeled seroprevalence estimates in 2015 and stepped this forward to estimate infections in 2019, dividing by the 2019 population size to give the 2019 incidence rate in each pixel 42 . Uncertainty in human LASV seroprevalence from the GLM was propagated forward to generate uncertainty in spillover incidence. Final non-aggregated estimates of spillover incidence from our model (at the pixel level) are shown in Fig. 1 , and aggregated estimates at the district level are shown in Supplementary Fig. B.1 . Estimates of spillover incidence in endemic districts are shown in Supplementary Figs. B.2 and B.3 .

Human-to-human transmission

We developed a stochastic branching process model to simulate infections arising from human-to-human transmission after spillover infection (Supplementary Appendix C.1 ). To account for uncertainty in estimated annual spillover incidence, 99 distinct transmission simulations were run, with each one using as inputs a set of LASV spillover estimates corresponding to a particular centile. Each set contains 183 values (one for each district), and the same values are used for each of the 10 years of simulation.

To account for seasonality observed in Lassa fever case reports, annual incidence estimates are distributed across each epidemiological year according to a beta distribution, as considered previously in Lerch et al. 43 . An outbreak tree was generated for each spillover event using an estimate of LASV’s basic reproduction number from the literature ( R 0  = 0.063) 43 , estimated from case data from a Lassa fever ward in Kenema Government Hospital, Sierra Leone, from 2010 to 2012 (ref. 44 ). Infections in each outbreak tree are distributed stochastically through time following estimates of LASV’s incubation and infectious periods 43 , and final outbreak trees are combined to generate the daily incidence of human-source infection in each district in the absence of vaccination. See Supplementary Table C.1 for LASV infection and transmission parameters.

Lassa vaccination campaigns

We included six vaccination scenarios in which limited doses of vaccine are allocated across specific subpopulations of West Africa (see Extended Data Table 2 and Supplementary Appendix C.2 for more details). Vaccine doses are allocated preferentially to populations perceived to be at greatest risk of Lassa fever—that is, those living in districts classified as Lassa fever endemic by the WHO 45 . In some scenarios, a small number of additional doses are allocated to non-endemic districts. In ‘constrained’ scenarios, the total number of vaccine doses is constrained to reflect limited capacity to produce, stockpile and deliver vaccine. For these scenarios, cholera is used as a proxy disease for assumptions relating to vaccine stockpile and target coverage based on recent campaigns in West Africa.

In our vaccination scenarios developed with these constraints in mind, we considered both reactive vaccination (targeting specific districts in response to local outbreaks) and preventive vaccination (mass vaccinating across entire countries or districts regardless of local transmission patterns). Vaccination was assumed to confer immunity for 5 years after a single-dose primary series, with a single-dose booster administered 5 years after the initial dose. Vaccination was applied in the model by ‘pruning’ zoonotic infections and ensuing person-to-person transmission chains—that is, by retrospectively removing infections directly and indirectly averted as a result of vaccination (see Supplementary Appendix C.3 for more details). We did not consider potential side effects of vaccination.

Health-economic burden of Lassa fever

A decision-analytic model describing the clinical progression of Lassa fever was developed to project the health and economic burden of disease and impacts of vaccination (Supplementary Appendix D.1 ). Inputs into this model from our spillover risk map and branching process transmission model include, for each year, district and vaccination scenario: the total number of LASV infections, the number of infections averted due to vaccination and the number of infections occurring in vaccinated individuals. The latter is included to account for vaccine preventing progression from infection to disease (Supplementary Appendix D.2 ). Probability distributions for model parameters were estimated using data from the literature and are described in detail in Supplementary Appendix D.3 . In brief, probabilities of hospitalization and death were estimated from reported hospital case data in Edo and Ondo, Nigeria, from 2018 to 2021; durations of illness before and during hospitalization were estimated from a prospective cohort study in a hospital in Ondo from 2018 to 2020; and hospital treatment costs were estimated from patients attending a specialist teaching hospital in Edo from 2015 to 2016 (Supplementary Table D.1 ) 5 , 8 , 38 .

Model outcomes

Lassa fever health outcomes estimated by our model include mild/moderate symptomatic cases, hospitalized cases, deaths, cases of chronic sequelae (sensorineural hearing loss) after hospital discharge and DALYs. Economic outcomes include direct healthcare costs paid out of pocket or reimbursed by the government, instances of catastrophic or impoverishing out-of-pocket healthcare expenditures, productivity losses, monetized DALYs and the VSL lost (a population-aggregate measure of individuals’ willingness to pay for a reduction in the probability of dying) 46 . We report societal costs as the sum of healthcare costs and productivity losses. All monetary costs are reported in 2021 international dollars ($), and future monetary costs are discounted at 3% per year. Impacts of vaccination are quantified from outputs of the health-economic model as the difference in projected outcomes across parameter-matched runs of the model with and without vaccination.

To calculate the TVC, we first summed relevant monetary costs for each simulation according to the economic perspective considered: healthcare costs and monetized DALYs, societal costs and monetized DALYs or healthcare costs and VSL. The TVC is then calculated as the monetary costs averted due to vaccination divided by the number of vaccine doses allocated, including booster doses and wasted doses, and discounting future vaccine doses at 3% per year.

In addition to our analysis of Lassa fever, we consider the emergence of ‘Lassa-X’, a hypothetical future variant of LASV with pandemic potential due to both elevated clinical severity and increased propensity for human-to-human transmission. We assume that the clinical characteristics of Lassa-X are identical to Lassa fever (including sequelae risk and hospital case–fatality ratio), except that Lassa-X is accompanied by a 10-fold increase in risk of hospitalization relative to Lassa fever. Then, to conceive plausible scenarios of Lassa-X transmission informed by empirical data, we assume that the inherent transmissibility of Lassa-X resembles that of Ebola virus during the 2013/2016 West Africa outbreak 47 , 48 . Ebola virus transmission was chosen as a surrogate for Lassa-X transmission because, like LASV, Ebola virus is a single-stranded RNA virus known to cause outbreaks in West Africa, results in frequent zoonotic spillover to humans from its animal reservoir, causes viral hemorrhagic fever and spreads from human to human primarily through contact with infectious bodily fluids. Based on this conceptualization of Lassa-X, we use a five-step approach to model its emergence and subsequent geospatial spread across West Africa and to estimate the health-economic impacts of reactive ‘100 Days Mission’ vaccination campaigns (described in detail in Supplementary Appendix F ).

Simulation and statistical reporting

For each of 99 runs of the LASV transmission model and 100 runs of the Lassa-X transmission model, health-economic outcomes were calculated via 100 Monte Carlo simulations, in which input parameters for the health-economic model were drawn probabilistically from their distributions (Supplementary Table D.1 ). In our base case, we assumed that the vaccine is 70% effective only against disease. However, we also included scenarios with vaccine that is 90% effective against disease, 70% effective against both infection and disease and 90% effective against both infection and disease. Final health and economic outcomes, as well as outcomes averted by vaccination, are reported as means and 95% UIs across all simulations over the 10-year time horizon of the model. In sensitivity analysis, we considered a 0% discounting rate, a lower risk of developing chronic sequelae subsequent to hospital discharge and either the same or lower hospitalization risk for Lassa-X relative to LASV. We also conducted a univariate sensitivity analysis to identify the parameters driving outcome uncertainty (see Supplementary Appendix D.4 for more details). Estimates of Lassa fever burden are reported in accordance with the Guidelines for Accurate and Transparent Health Estimates Reporting (GATHER) statement. A GATHER checklist is provided in Supplementary Appendix H .

Role of the funder

The Coalition for Epidemic Preparedness Innovations (CEPI) commissioned this analysis, and CEPI internal Lassa fever experts were involved in study design by providing knowledge on input parameters and fine-tuning realistic scenarios for vaccine rollout. An earlier version of this work was provided as a report to CEPI.

Reporting summary

Further information on research design is available in the Nature Portfolio Reporting Summary linked to this article.

Data availability

The minimum dataset required to run our code and reproduce results is available at https://doi.org/10.5281/zenodo.12751191 (ref. 49 ).

Code availability

The code underlying our model is available at https://doi.org/10.5281/zenodo.12751191 (ref. 49 ). Data were collected, compiled, analyzed and simulated using R version 4.3.3. Simulations were dispatched using HTCondor version 10.0.4.

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Acknowledgements

This work was conducted by the OxLiv Consortium and funded by the Coalition for Epidemic Preparedness Innovations (CEPI) through Vaccine Impact Assessment project funding. We acknowledge the CEPI project team (project lead: A. Deol and project co-lead: C. Mukandavire) for their continuous support and helpful discussions and the project’s external advisory team for their invaluable feedback. T.D.H. thanks the Li Ka Shing Foundation for institutional funding. K.B.P. is supported by the Medical Research Foundation (MRF-160-0017-ELP-POUW-C0909). C.A.D. is funded by the National Institute for Health Research (NIHR) Health Protection Research Unit (HPRU) in Emerging and Zoonotic Infections (200907), a partnership among the United Kingdom Health Security Agency (UKHSA), the University of Liverpool, the University of Oxford and the Liverpool School of Tropical Medicine. D.W.R. is supported by a Medical Research Council (MRC) UK Research and Innovation (UKRI)/Rutherford Fellowship (MR/R02491X/1 and MR/R02491X/2) and a Sir Henry Dale Research Fellowship (funded by the Wellcome Trust and the Royal Society) (220179/Z/20/Z and 220179/A/20/Z). This research was supported by the Quantitative and Modelling Skills in Ecology and Evolution (QMEE) Centre for Doctoral Training (CDT), funded by Natural Environment Research Council (NERC) grant NE/P012345/1 (L.A.A.); the MRC Centre for Global Infectious Disease Analysis (L.A.A. and C.A.D.); the HPRU in Emerging and Zoonotic Infections (C.A.D.) and the Trinity Challenge (the Sentinel Forecasting project) (K.E.J., R.G. and D.W.R.). D.A.W. is funded by the National Institutes of Health (National Institute of Allergy and Infectious Diseases: R01AI135105). We would like to thank A. Lerch for personal communications and for providing code that inspired our LASV transmission model. We thank M. Todd from Dreaming Spires for assisting in optimizing the speed of our stochastic branching process model for Lassa. We acknowledge I. Smith, Head of Research Software Engineering at University of Liverpool IT Services, for his help running simulations using HTCondor. We thank A. Desjardins and A. Borlase for early discussions on Lassa dynamics, N. Salant for beta testing our code and C. Nunes-Alves for providing helpful comments on an earlier draft. The views expressed are those of the authors and not necessarily those of the institutions with which they are affiliated.

Author information

These authors contributed equally: David R. M. Smith, Joanne Turner.

Authors and Affiliations

Nuffield Department of Population Health, Health Economics Research Centre, University of Oxford, Oxford, UK

David R. M. Smith & Koen B. Pouwels

Department of Mathematical Sciences, University of Liverpool, Liverpool, UK

Joanne Turner & Emily J. Nixon

Department of Livestock and One Health, Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool, UK

Joanne Turner

Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford, UK

Patrick Fahr

Department of Genetics, Evolution and Environment, Centre for Biodiversity and Environment Research, University College London, London, UK

Lauren A. Attfield, Rory Gibb & Kate E. Jones

Department of Infectious Disease Epidemiology, Imperial College London, London, UK

Lauren A. Attfield & Christl A. Donnelly

Independent consultant, Edinburgh, UK

Paul R. Bessell

Department of Statistics, University of Oxford, Oxford, UK

Christl A. Donnelly

Pandemic Sciences Institute, University of Oxford, Oxford, UK

Science Department, The Natural History Museum, London, UK

David W. Redding

Irrua Specialist Teaching Hospital, Irrua, Nigeria

Danny Asogun

Federal Medical Centre, Owo, Nigeria

Oladele Oluwafemi Ayodeji

Alex Ekwueme Federal University Teaching Hospital Abakaliki, Abakaliki, Nigeria

Benedict N. Azuogu

Institute for Global Health and Infectious Diseases, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC, USA

William A. Fischer II & David A. Wohl

Nigeria Centre for Disease Control and Prevention, Abuja, Nigeria

Kamji Jan & Adebola T. Olayinka

Linksbridge SPC, Seattle, WA, USA

Andrew A. Torkelson & Katelyn A. Dinkel

Big Data Institute, Li Ka Shing Centre for Health Information and Discovery, University of Oxford, Oxford, UK

T. Déirdre Hollingsworth

Nuffield Department of Medicine, NDM Centre for Global Health Research, University of Oxford, Oxford, UK

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Contributions

D.R.M.S. and J.T. contributed equally to this work and share first authorship, and E.J.N., K.B.P. and T.D.H. contributed equally to this work and share senior authorship. E.J.N., K.B.P. and T.D.H. conceived of the study and acquired funding. A.A.T. administered the project. D.A., O.O.A., B.N.A., W.A.F., K.J., A.T.O. and D.A.W. provided expert input on Lassa fever epidemiology. L.A.A. and D.W.R. developed the methods to estimate zoonosis incidence, which C.A.D., R.G. and K.E.J. supervised. E.J.N., K.B.P. and T.D.H. supervised all other aspects of the study. J.T. developed the branching process model and pruning algorithm, with support from D.R.M.S. D.R.M.S. developed the health-economic model, with support from P.F., developed the Lassa-X model and prepared final results, figures and tables, with support from J.T. and P.R.B. The original draft was written by D.R.M.S., J.T., P.F., C.A.D., A.A.T., E.J.N., K.B.P. and T.D.H. All authors reviewed, edited and approved the final draft.

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Correspondence to David R. M. Smith .

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Extended data

Extended data fig. 1 model schematic..

See Methods for details and Supplementary figure D.1 for a schematic of the decision-analytic model describing disease progression. Pruning in step 5a refers to retrospectively removing infections averted due to vaccination from simulated transmission chains. LASV = Lassa virus .

Extended Data Fig. 2 Impacts of a Lassa vaccine effective against infection and disease.

( A ) The mean cumulative number of LASV infections averted due to vaccination across the 15 countries included in the model, comparing vaccine efficacy against infection and disease of 70% (blue) versus 90% (red) across the six considered vaccination scenarios (panels). 95% uncertainty intervals are indicated by shading. ( B ) The mean cumulative number of infections averted over ten years under each vaccination scenario in the four countries classified as high-endemic (Guinea, Liberia, Nigeria and Sierra Leone). 95% uncertainty intervals are indicated by error bars (n = 9,900). ( C ) The mean cumulative incidence of infections averted over ten years per 100,000 population under each vaccination scenario in the same four countries. 95% uncertainty intervals are indicated by error bars (n = 9,900). ( D ) The mean daily number of infections averted by a vaccine with 70% efficacy against infection and disease over the first three years of vaccine rollout, in three distinct districts under four selected vaccination scenarios. 95% uncertainty intervals are indicated by shading.

Supplementary information

Supplementary appendices a–i, figs. b and d–g and tables c–e, g and h., reporting summary, rights and permissions.

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Smith, D.R.M., Turner, J., Fahr, P. et al. Health and economic impacts of Lassa vaccination campaigns in West Africa. Nat Med (2024). https://doi.org/10.1038/s41591-024-03232-y

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DOI : https://doi.org/10.1038/s41591-024-03232-y

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