Medical Abbreviations: WTF (What They’re For) and OMG (Optimal Management Guide)

Last updated: 2 November, 2022

If you work with medical text, you’re familiar with how authors like to salt their text with SLTs (Simple Lexical Tools) representing SLTs (Standard Learned Terms). Sometimes, however, these are SLT (Single, Limited, or Transient) in use, and much of the time their real function is just as SLTs (Shiny Little Toys).

Why does medical literature use abbreviations—including acronyms and initialisms—so much? No doubt in part it’s because they seem technical and important. And they give a certain thing-ness to what they name: it’s not just some passing observation; it has its own constellation in the heavens of the literature. They also add brevity: “AS,” for example, is 20 characters shorter than “ankylosing spondylitis” (and it’s easier to spell).

However, although brevity is famously the soul of wit, medical conditions are no laughing matter, and too much brevity can be the soul of “What?” Abbreviations are seldom transparent, seldom widely known, and often ambiguous.

What’s more, they’re overused. A 2020 study by Adrian Barnett and Zoe Doubleday surveyed more than 24 million articles and 18 million abstracts published between 1950 and 2019, and found that 79% of acronyms appeared fewer than 10 times. Of more than a million different acronyms in their data, only 0.2% were used regularly.

Which means there are a lot of hard-to-decipher little clusters of letters out there getting in the way of information by making more, not less, mental work for readers. When editing documents, your goal is to help the reader get the information as effectively as possible. Here are 10 pearls of wisdom to help the medicine—or the medical information, anyway—go down well, with minimal misunderstanding of abbreviations.

1. First, Do No Harm to the Words

Don’t brutalize the words to make a cute abbreviation. Yes, we’re looking at you, people who give clinical trials their names—sure, you might think INSIGHT is a splendid and memorable abbreviation to use, but when it stands for “follow-up INvestigation of excesSIve weiGHT gain,” who the heck is going to make the connection or be able to remember it? But we’re also looking at the rest of you who make handy abbreviations for key concepts. If the study is looking at mitochondrial leakage caused by Streptococcus pneumoniae–secreted hydrogen peroxide, you won’t want to use the whole phrase every time, but you also shouldn’t anoint it “StrypeMiLk” (for STReptococcus pneumoniae–secreted hYdrogen Peroxide–induced MItochondrial LeaKage). (Don’t worry, that one is a made-up example.)

2. Don’t Skip the Introduction

Make sure to define the abbreviation unless it’s one of a very small set that truly need no introduction. When in doubt, define! Clinical protocols submitted for regulatory approval will sometimes even define “DNA” and “AIDS,” so, unless your style manual tells you otherwise, err on the side of caution. Define an abbreviation the first time you use it, so the reader isn’t left hanging—this is something PerfectIt™ will alert you about when you run its “Abbreviations” check. And if you introduce the abbreviation but then go a long time before re-using it, consider defining it again—readers don’t have infinite memories.

3. Don’t Pop Them Like Candy

Abbreviations are information in pill form, but don’t overprescribe them. An abbreviation that’s used only the one time it’s defined doesn’t save space, it wastes it, and it squanders the reader’s mental energy too. When you run a PerfectIt™ check on abbreviations, it will let you know if you’ve done this. You may want to go further, too: even if you use an abbreviation two or three times, it might make more bother than it’s worth, especially if the uses are so far apart the reader has to go back and look up what it stands for.

4. Use the Same Abbreviation for the Same Thing

This means don’t use one abbreviation (e.g., SLT) to mean more than one thing, but it also means don’t use more than one abbreviation to mean the same thing – PerfectIt™ will check for both of these. And this is not just about choosing either “AoCD” or “ACD” but not both for “anemia of chronic disease”; it’s also about using either “HbA1c” or “A1C” for “hemoglobin A1c” but not first one and then the other. It doesn’t matter that you might do that in conversation for convenience; an abbreviation is already a short form and doesn’t need an even shorter form. Inconsistency can be distracting and confusing.

5. Watch Out for Ambiguity

Even if you use an abbreviation to mean only one thing, if other people often use it to mean something else, you should be very careful about using it. For example, PCU can stand for “progressive care unit,” “primary care unit,” “protective care unit,” or “palliative care unit,” and though you may define your use of it early on in the paper, the reader might forget that several pages later and come to a badly inaccurate understanding. This article by Neil M. Davis includes some very useful lists of ones to watch out for. You should also watch out for ones that are commonly used as informal abbreviations for impolite things, lest your readers break out in laughter. This includes not just well-known ones like WTF and OMG but also medical insider ones such as FLK (funny-looking kid) or GOK (God only knows)—this is where an advance reader or two from the target audience can come in handy.

6. Be Consistent, Period

We’ve already said “be consistent,” but there’s even more to consistency than just having one abbreviation for one thing. There’s also consistency of style. Make sure your micrograms aren’t sometimes mcg and sometimes µg; make sure you are consistent about use of a space (or not) before unit abbreviations (e.g., 20 mg or 20mg); make sure that if you superscript or subscript something you do it everywhere (e.g., HbA1c). And in initialisms, either put periods in all of them or don’t put periods in any of them (check your chosen style reference manual to find out which it prefers). It’s weird and distracting to see variations such as “Usually a PCP is the first HCP to identify signs of M.S. or C.F.S. in a patient.” This is another thing PerfectIt™ can check for you.

7. Don’t Be Redundant

Editors know to fix the redundancies in “use your PIN number in an ATM machine” (because PIN = “personal identification number” and ATM = “automated teller machine”). Similarly, medical editors need to watch out for “CFS syndrome” (“chronic fatigue syndrome syndrome”) and for “Dr. Patna Chaudhry, MD”: “MD” automatically means the person is “Dr.” so just use one or the other.

8. Get Your Journals Right

Ah, those journal name abbreviations, staples of citations in the sciences! If you work with them, you’ll know that J stands for “Journal,” and you may be pretty sure you know the other usual abbreviations… but are you sure? You might get away with not knowing that the official citation abbreviation for the New England Journal of Medicine is N Engl J Med, not NEJM, but if you put J Inh Met D instead of J Inherit Metab Dis for the Journal of Inherited Metabolic Disease, readers who want to follow your references (and there will be some!) might run into some trouble figuring it out.

9. Consider Your Audience

Who’s going to be reading this? If the document is for laypeople—consumer-directed information for a drug, for instance, or a disease information leaflet, or a press release—assume they won’t know what standard abbreviations mean. Spend the extra letters to say “twice-a-day dosing” rather than “bid,” and “heart attack” rather than “MI.” If that seems very low-level in the context of the document, then the document is probably too high-level for a general audience and should be reworked. This is people’s health here: first do not harm, and there’s no harm in being as clear as possible.

10. Double-Check Your Work

You may feel that you have a grip on all your abbreviation usages, and that you’ve been careful, but with so many things going on in a medical paper or other healthcare document, including revisions, little slips are easy. Do a pass to double-check. An editing tool such as PerfectIt™ will make this more efficient and effective. The “Abbreviations” check in PerfectIt™ looks at anything that seems to be an acronym or initialism and will let you know if a term is used only once, used or spelled inconsistently, defined several ways or not at all, or defined somewhere other than the first usage. It’s still up to you to look at what it shows you and use your judgment but, if you’re checking acronyms professionally, it quickly pays for itself in the time that it saves. You can test PerfectIt for free with its 14-day free trial.