EMQ’s are being increasingly used in research and papers have recently been published on their success in the USMLE. Its likely that many medical schools will adopt this N from many approach. An EMQ is simple: its a series of typically 6-10 answers, used a number of times with different question stems.They first cropped up in 1993 after work by Case and Swanson. Read more about EMQ’s and their development here.
Distracters are being used to throw students off the scent, and in some ways discriminate from good and bad students. An example would be describing a history of a rash affecting the flexor surfaces and giving on e of the answers as psoriasis. Seeing the two together can lead to the assumption this is the correct answer. This is an example of a good discriminator, but EMQs can easily be written in such a way that the more capable student gets it wrong!
“A 64 year old homeless man presents after being found exposed under a bush shelter by paramedics. He is ‘tided over the night’ by the emergency department staff with an IVI of 5% dextrose. The next morning he is confused, and ataxic. On examination he has nystagmus. Which of the following is treatment is most likely to be effective?”
Students classically then have to pick from a range of answers:
- Gluten free diet
- Peg Interferon alpha
- Vitamin B Complex
Here’s the Answer from the main site:
“Nystagmus, and ataxia are features of cerebellar disease, with the addition of confusion this triad is suggestive of Wernickes Encephalopathy (vitamin B1 deficiency- thiamine). Risk factors: poor nutrition (+/- alcohol).
Thiamine is important in carbohydrate metabolism and the Krebs cycle: it’s vital to remember that dextrose presents a carbohydrate load, the excess of which cannot be effectively metabolised , leading to cell death.
Hence the treatment: Vitamin B complex: initially this is given as Intravenous Pabrinex © for 48-72 hours.”
The EMQ here does a number of things: You could use your knowledge of drugs alone to answer the question: An antiviral (acivlovir), quinalone antibiotic (ciprofloxacin), an antispasmodic (buscopan), a Proton pump inhibitor (omeprazole) a gluten free diet (!), etc.
Aciclovir would initially seem attractive for a possible encephalitis- there are some things that fit: confusion, other CNS signs? This is a form of a distracter-look at the history, and the role of the glucose drip.Here the answer has been worked through by correctly recognise the triad of opthalmoplegia, confusion and ataxia that isin keeping with the diagnosis of Wernickes.
So, we can see that EMQs look initially pretty intuative, but more are being written, and expect them to be coming to an exam near you soon.
You can work through some examples of EMQ’s to prepare for your medical finals with different question structures on the subscription section of our site.