Abbreviations are a convenience, a time saver, a space saver, and a way of avoiding the possibility of misspelling words. However, a price can be paid for their use. Abbreviations are sometimes not understood. They can be misread, or are interpreted incorrectly. … The person who uses an abbreviation must take responsibility for making sure that it is properly interpreted.—Neil M. Davis1
Abbreviations are used widely in medical articles, and great care should be taken to provide expansions that define these abbreviations. The AMA Manual of Style includes a straightforward rule regarding the use of abbreviations: Define abbreviations at first mention by providing the expanded term first, followed by the abbreviation in parentheses, and the abbreviation is used thereafter.
But for every rule, there are exceptions.
• Avoid creating abbreviations for terms that are easy to spell out and do not take up a lot of space. For example, it is not advisable to abbreviate “catheter ablation” as “CA” or “immune response” as “IR.” Also, avoid using too many abbreviations in any one article.
• If a term is better known as an abbreviation, provide the abbreviation first with the definition following in parentheses. “The TUNEL (terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labeling) staining assay was carried out using an apoptosis detection kit.”
• It is inelegant to begin sentences with abbreviations, unless the expansion is so unwieldy that using the abbreviation makes sense. The previous example, TUNEL, also works here. Rather than begin a sentence with the cumbersome expansion, it is acceptable to begin the sentence with the abbreviation TUNEL.
• Abbreviations should not be introduced in headings. If an abbreviation is being used for the first time in a heading, expand the abbreviation in the heading; then, at first mention in the running text after the heading, expand the abbreviation again, with the abbreviation following in parentheses. Use the abbreviation thereafter.
• Some very common abbreviations do not require expanding at first mention, such as AIDS, TNM, UV, and CD-ROM. A complete list of these abbreviations is provided in section 14.11, with those that do not require expansion denoted by an asterisk.
• The efficiency of using an abbreviation is lost if the abbreviation is used only one time, so as a rule of thumb, introduce an abbreviation only if it is used at least 2 or 3 times.
Items of Note:
• Tables, figures, and abstracts are treated as separate items from the text, so abbreviated terms must be reexpanded in each of these items.
• Use the appropriate article (a or an) before an abbreviation according to the sound following the article (eg, a UN resolution, an HMO plan).
• Use a lowercase s (and no apostrophe) when making abbreviations plural (eg, NSAIDs).—Lauren B. Fischer
1. Davis NM. MEDical ABBREViations: 28,000 Conveniences at the Expense of Communication and Safety. 13th ed. Warminster, PA: Neil M Davis Associates; 2007:1.