How to use acronyms

Acronyms are abbreviations formed by the first letters or components of a word or phrase. They make life easier as a long term can be condensed into a short term that's easier to pronounce and write. No one likes to say or write "cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy", but it's no problem to say "CADASIL".

However, acronyms do reduce comprehension, particularly when they are novel / not generally accepted and as such, they should be used sparingly. 

If one were being pedantic, then actually most medical acronyms in English are initialisms, as they are prounced as individual letters rather than a word (e.g. AMI is said "a-em-eye" and not "aimee"). NASA is an example of a true acronym as it is pronounced as a word "nasa" rather than "en-a-es-a". All that having been said, most folk are now using the term acronym for both, and if you are reading this you are probably not getting invited to many parties anyway, so best to let it go. 

It can be tempting to abbreviate longer terms for repeated use in the remaining text ("convenience acronyms"). This practice is widely used in medical textbooks and journal articles, stemming in large part, from word count and page number limits. Unfortunately, acronyms reduce readability and comprehension, particularly when they are unfamiliar.  Thus, since we don't need to worry about word length and readers often skip down to the middle of an article, we only use abbreviations or acronyms if they are widely known and used.

If an acronym is thought to be necessary (see above), the first time in a text it should be written in full with the acronym in parentheses. From there on the abbreviation/acronym can be used throughout.

When introducing the acronym/abbreviation it should be immediately after the abbreviated term, not at the end of a longer phrase that includes non-abbreviated parts, e.g.:

  • Cytomegalovirus (CMV) encephalitis is one of the more common opportunistic infections in patients with HIV
    > encephalitis is not abbreviated, so "(CMV)" ends up in the middle of the term

Acronym use in article titles

Either the acronym or the full term should be used in an article's title, not both, as this gets a bit crowded. Whether to use the acronym will depend on the degree of acceptance and use of the acronym. The acronym should be in the title when in practice the acronym is the preferred term and the full term is hardly ever used. In all other cases, write it in full in the title and introduce the acronym in the first sentence of the article.

  • Acronym the only used term in daily practice:
    Article title: CADASIL
    First sentence: Cerebral Autosomal Dominant Arteriopathy with Subcortical Infarcts and Leukoencephalopathy (CADASIL) is an autosomal dominant vascular dementia, linked to a gene on chromosome 19
  • The full term still commonly known and (perhaps to a lesser extent) used:
    Article title: Creutzfeldt-Jakob disease
    First sentence: Creutzfeldt-Jakob disease (CJD) is a spongiform encephalopathy that results in a rapidly progressive dementia and other non-specific neurological features

When using an acronym in a sentence, and needing to make the term plural, then an 's' should be appended to the acronym, without an apostrophe (read more about use of apostrophes).

In other words: 

  • correct: AMIs, MCAs, ELSTs
  • incorrect:  AMI's, MCA's, ELST's

If the acronym ends with an S, the same rule applies: 

  • correct: SOSs
  • incorrect:  SOS's, SOSes

Note: This is a topic of some contention and various style guides adopt different conventions. Please don't get upset by this. We have chosen this one as a common and simple option. 

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Article information

rID: 34320
Synonyms or Alternate Spellings:
  • Initialisms

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