APA Usage and Style Guidelines


APA rules for abbreviations state:

  • Acronyms and abbreviations must be spelled out completely on initial appearance in text.
  • Use only if abbreviation is conventional, is apt to be familiar, will save considerable space, and will prevent cumbersome repetition.
  • Avoid beginning a sentence with an acronym or an abbreviation.

For further information, see pages 111-114 in the Publication Manual.


APA rules for capitalization state:

  • Capitalize all words of four letters or more in titles of books and articles in text.
  • Do not capitalize names of laws, theories, and hypotheses except for proper nouns.

For more information, see pages 101-104 in the Publication Manual.


APA rules for hyphenation state:

  • For compound words not in the dictionary, use hyphens for clarity rather than omit them.
  • Hyphenate compound adjectives that precede the noun they modify:
    • role-playing technique
    • two-way analysis
    • middle-class families
  • Do not hyphenate a compound adjective if its meaning is established or it cannot be misread:
    • grade point average
    • sex role difference

For more information, see pages 97-100 in the Publication Manual.


APA rules for numbers state:

  • Use figures for numbers 10 and above (12 of the subjects); for numbers above and below 10 grouped for comparison (2 of 16 responses); for numbers representing time, dates, and age (3 years ago, 2 hr 15 min); for numbers denoting a specific place in a series, book, or table (Table 3, Group 3, page 32).
  • Use words for numbers below 10 that do not represent precise measurements (eight items, nine pages); for numbers beginning a sentence, title, or heading (Forty-eight percent responded; Ten subjects improved, and 4 subjects did not.).

See pages 99-105 in the Publication Manual.


APA rules for quotations state:

  • Incorporate quotations of less than 40 words in the text with double quotation marks.
  • Place quotations of 40 or more words in a double-spaced block, indented five spaces from left margin. Do not use quotation marks with a blocked quotation.
  • If quoting more than one paragraph, indent the first line of each paragraph five additional spaces from the left margin (for a total of ten spaces).
  • A page number always immediately follows a quotation, even when the author and date precede it: Lu (1990) found that “several hypotheses were partially supported” (page 48).

See pages 170-171 in the Publication Manual.