APA Style uses two types of capitalization for titles of works (such as paper titles) and headings within works: title case and sentence case.
In title case, major words are capitalized, and most minor words are lowercase. In sentence case, most major and minor words are lowercase (proper nouns are an exception in that they are always capitalized).
- major words: Nouns, verbs (including linking verbs), adjectives, adverbs, pronouns, and all words of four letters or more are considered major words.
- minor words: Short (i.e., three letters or fewer) conjunctions, short prepositions, and all articles are considered minor words.
Sentence case capitalization is covered in Section 6.17 of the APA Publication Manual, Seventh Edition

This guidance has been expanded from the 6th edition.
How to implement sentence case
In sentence case, lowercase most words in a title or heading. Capitalize only the following words:
- the first word of the title or heading
- the first word of a subtitle
- the first word after a colon, em dash, or end punctuation in a heading
- nouns followed by numerals or letters
- proper nouns (such as the names of racial or ethnic groups)
When to use sentence case
Use sentence case for the following:
- titles of articles, books, reports, webpages, and other works in reference list entries, even if title case was used in the original work
Knapp, S. J. (2019). Suicide prevention: An ethically and scientifically informed approach. American Psychological Association. https://doi.org/10.1037/0000145-000
Scott, T. N., Gil-Rivas, V., & Cachelin, F. M. (2019). The need for cultural adaptations to health interventions for African American women: A qualitative analysis. Cultural Diversity and Ethnic Minority Psychology, 25(3), 331–341. https://doi.org/10.1037/cdp0000228
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