APA Style Abbreviations

Throughout your paper, you must decide whether to spell out an expression every time it's used, or spell it out the first time and abbreviate it throughout the rest of the paper. APA suggests you use the abbreviation only if it is conventional and the reader is likely to be familiar with the abbreviation, and if it can save you a considerable amount of time and space, and spare your reader some avoidable repetition. Some abbreviations are already used as words (IQ, REM, HIV) and others may be well-known in your field of study; nevertheless, you should still provide a definition or explanation the first time you use the abbreviation. Latin abbreviations (i.e., e.g., etc.) may be use in parentheses, but use the English versions of the terms in your text. Scientific abbreviations (dB, km, rpm, kHz) may be used without explanation.