Supplemental materials in APA 7 Style: when to use them

What supplemental materials are

Supplemental materials are files that accompany a journal article and are published online only. They make useful content available when it does not fit well within the manuscript pages.

They are not normally part of a student paper. A class assignment usually uses an appendix when supporting material must remain within the document.

Appendix or supplemental material

Appendix	Supplemental material
Part of the paper	Published as a separate online file
Works well on a printed page	May require audio, video, data, or downloads
Included after references and other end matter	Submitted with the manuscript under journal instructions
May appear in student papers	Used mainly with professional publications

Do not choose between them based only on length. Consider how readers need to use the content.

What can be published as a supplement

Examples include:

• audio or video files
• animations
• lengthy computer code
• detailed mathematical or computational models
• tables too large for a page
• complete protocols
• expanded method descriptions
• data files
• downloadable templates and worksheets

The file should help readers understand or use the work. It should not become a place for unreviewed details that do not support the article.

How to mention it in the text

Briefly describe the material and explain its purpose. The journal connects the published article with the accepted files.

Example:

The supplemental materials include the template used to record study sessions and a file containing the variable definitions.

If the mention would interrupt the argument, it may appear in a content footnote.

How to prepare the files

1. Check the file types and limits accepted by the journal.
2. Use descriptive file names.
3. Include enough context to interpret each item with the article.
4. Review data, labels, permissions, and copyright.
5. Confirm that files open without unnecessarily specialized software.
6. Add captions, transcripts, alternative text, or other accessibility support when appropriate.

Supplemental files may be published without detailed copyediting. Review them as carefully as the main manuscript.

Data and research files

A complete data set may also be deposited in a repository. In that case, it may need its own data set reference. The choice depends on journal instructions, ethical commitments, and the most stable way to share the information.

Checklist

• You confirmed that the submission accepts supplemental materials.
• The content genuinely needs a separate file.
• Each file can be understood alongside the article.
• The formats are accessible and accepted by the journal.
• You reviewed sensitive information, permissions, and copyright.
• The text briefly describes the material that is available.