Counterpoint: Chunking theory and why medical mnemonics can be useful.

In Knowledge Translation, Tiny Tips by Teresa Chan5 Comments

By Teresa Chan, MD    |    Peer-reviewed by Brent Thoma, MD

Lately, I’ve been pondering about the role of mnemonics.

Join me as I wax philosophical and dig into the education theory behind why we’re tempted by these tiny packages of information.


Why am I thinking about Chunking?

I’ve been reading a lot about the psychological sciences right now as I have been working on my thesis proposal.  Some of the great work done was on Chessmasters and their inordinate ability to remember chess boards at play.  This lead to some theories around a phenomenon now known as ‘chunking’.

Then, I was cc’d on a tweet December 15, 2013.

It brought me to a post by ‘Compound Fracture’ that stated:

There comes a point in medical education where mnemonics become a crutch or are even harmful to your knowledge. You want to be able to understand a disease state enough to be able to reason through the clinical presentations rather than trying to remember what the ‘E’ in CHORD ITEM stands for.

At first glance, I can see what this person means.  You shouldn’t supplant clinical reasoning with random medical mnemonics.  And yet, for my thesis I have delved quite deeply into the psychological and educational research around diagnostic reasoning… and I’m not sure that this ‘gut reaction’ is evidence based.  So, now it is time for, another Counterpoint!


Dear ‘Compound Fracture’:

Your point is well taken, but you could say this about nearly any educational intervention if it ends up supplanting actual thinking and reasoning. But mnemonics have their role as well and a huge basis in the psychological literature.

‘Chunking’ is a memorization strategy defined by Miller […]. He found that experts chunked things together (found patterns, saw them, used them) so that they could memorize more.

If you are relying on mnemonics to remember everything… I agree that is unreasonable and foolhardy. In fact, I would argue that in clinical practice if you’re trying to remember a letter in a mnemonic, just look it up – for you and your patient’s sake.

However, for testing (and for when you are being pimped) I think there is a role for chunking (actually I think we should really just change the tests so you don’t have to use mnemonics…but I digress). You can read my related rant here (My first Counterpoint).

Medical Mnemonics for tests:

I think in certain cases there is little harm to be done with using good, evidence-based approaches to conquering your education goals. We are often Evidence-based with our medicine, but funnily enough, we don’t encourage this same voracity of knowledge translation around other key sciences that can help us. I would suggest that learning to create MEANINGFUL mnemonics can be useful to cue your brain to connect disparate and random concepts (e.g. a list of 8 drugs that cause methemoglobinemia). In the end, yes, you COULD go back to first principles and learn EVERY SINGLE pharmacokinetic and structural similarity between the 8 drugs or you might create a mnemonic for rapid recall. Pragmatically, for many high-stakes exams (e.g. Boards or Royal College examinations).

Medical Mnemonics For Clinical Practice:

Like I said above, if you’re using a mnemonic and can’t remember you should probably just look it up. However, there can be a role for mnemonics to help you remember a checklist (e.g. the SIGNOUT handover mnemonic, SBAR mnemonic, FAST HUG for ICU safety), and that can be useful.

Bottom Line on Medical Mnemonics:

I think that the educational evidence suggests that mnemonics can be useful and you can consider using them (especially in time-limited testing scenarios), but not relying on them in clinical practice.



Thanks to ‘Compound Fracture’ for being skeptical about mnemonics. It is important to be skeptical about things.  Education needs to critiqued with the save voracity as medicine.  Taking things for granted is probably the way we got into a lot of ruts (e.g. teaching the way we were taught).  With the dawn of EBM, this became less and less so.  And now…. we’re on the verge of Evidence Based Medical Education (EBME!), so let’s get out there – research & discuss about education topics!  Question things!  But if there’s evidence, let’s start using it.


P.S. The post script is inspired by one of my friends and mentors Dr. Ken Milne (The Skeptic’s Guide to Emergency Medicine). Let’s get medical educators skeptical as well! 😀

Title Picture Credit: Attribution-NoDerivs 2.0 Generic (CC BY-ND 2.0) by Jon Fingas (

Teresa Chan

Senior Editor at CanadiEM
Emergency Physician. Medical Educator. #FOAMed Supporter, Producer and Researcher. Chief Strategy Officer of CanadiEM. Associate Professor, Division of Emergency Medicine, Department of Medicine, McMaster University.