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APA Headings and Seriation

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Note:  This page reflects the latest version of the APA Publication Manual (i.e., APA 7), which released in October 2019. The equivalent resource for the older APA 6 style  can be found here .

APA Style uses a unique headings system to separate and classify paper sections. Headings are used to help guide the reader through a document. The levels are organized by levels of subordination, and each section of the paper should start with the highest level of heading. There are 5  heading levels  in APA. Regardless of the number of levels, always use the headings in order, beginning with level 1. The format of each level is illustrated below:

Thus, if the article has four sections, some of which have subsections and some of which don’t, use headings depending on the level of subordination. Section headings receive level one format. Subsections receive level two format. Subsections of subsections receive level three format. For example:

Method  (Level 1)

Site of Study  (Level 2)

Participant Population  (Level 2)

Teachers  (Level 3)

Students  (Level 3)

Results  (Level 1)

Spatial Ability  (Level 2)

Test One  (Level 3)

     Teachers With Experience.  (Level 4)

     Teachers in Training.  (Level 4)

     Teaching Assistants .  (Level 5)

Test Two  (Level 3)

Kinesthetic Ability  (Level 2)

In APA Style, the Introduction section never gets a heading and headings are not indicated by letters or numbers. For subsections in the beginning of a paper (introduction section), the first level of subsection will use Level 2 headings — the title of the paper counts as the Level 1 heading. Levels of headings will depend upon the length and organization of your paper. Regardless, always begin with level one headings and proceed to level two, etc.

Special headings called section labels are used for certain sections of a paper which always start on a new page.

• Paper title
• Appendix A (and so on for subsequent appendices)

These labels should be positioned on their own line at the top of the page where the section starts, in bold and centered. 

APA also allows for seriation in the body text to help authors organize and present key ideas. For lists where a specific order or numbered procedure is necessary, use an Arabic numeral directly followed by a period, such as:

On the basis of four generations of usability testing on the Purdue OWL, the Purdue OWL Usability Team recommended the following:

• Move the navigation bar from the right to the left side of the OWL pages.
• Integrate branded graphics (the Writing Lab and OWL logos) into the text on the OWL homepage.
• Add a search box to every page of the OWL.
• Develop an OWL site map.
• Develop a three-tiered navigation system.

Numbered lists should contain full sentences or paragraphs rather than phrases. The first word after each number should be capitalized, as well as the first word in any following sentence; each sentence should end with a period or other punctuation.

For lists that do not communicate hierarchical order or chronology, use bullets:

In general, participants found the user-centered OWL mock up to be easier to use. What follows are samples of participants' responses:

• "This version is easier to use."
• "Version two seems better organized."
• "It took me a few minutes to learn how to use this version, but after that, I felt more comfortable with it."

Authors may also use seriation for paragraph length text.

For seriation within sentences, authors may use letters:

On the basis of research conducted by the usability team, OWL staff have completed (a) the OWL site map; (b) integrating graphics with text on the OWL homepage; (c) search boxes on all OWL pages except the orange OWL resources (that is pending; we do have a search page); (d) moving the navigation bar to the left side of pages on all OWL resources except in the orange area (that is pending); (e) piloting the first phase of the three-tiered navigation system, as illustrated in the new Engagement section.

Authors may also separate points with bullet lists:

On the basis of the research conducted by the usability team, OWL staff have completed

• the OWL site map;
• integrating graphics with text on the OWL homepage;
• search boxes on all OWL pages except the orange OWL resources (that is pending; we do have a search page);
• moving the navigation bar to the left side of pages on all OWL resources except in the orange area (that is pending);
• piloting the first phase of the three-tiered navigation system, as illustrated in the new Engagement section.

If your bulleted list is part of the sentence and is not preceded by a colon, treat the bullets like a part of the sentence, adhering to standard capitalization and punctuation. This option is helpful for complex or longer bulleted sentences that may be more difficult to read without the aid of punctuation. For items in a bulleted list that are phrases rather than sentences, no punctuation is necessary.