Thursday 21 July 2011

Why Medical Schools use the MCAT...

...and how is medicine like hardcore pornography?

Another exam! …Don’t like it? I heard McDonalds is hiring.

The academic world is full of exams, and the MCAT is the first of many exams throughout one’s medical training.  Furthermore, (written) tests such as the MCAT are very objective measure; and therefore, we assume they are a fair way to assess applicants.

Like any test – if you do well, you wish medical schools placed greater weight on your MCAT scores; and if you did not do so well, you think… what the hell do I.C.E. tables and a short story on abstract art have to do with real-world medical practice anyway?

The jury is in:
You don’t have to look very far on PubMed for publications praising the predictive value of the MCAT. Without going into too much detail, your MCAT score is a predictor of your performance throughout medical school, both in Canada and the US1,2.

Well this is simple right? High MCAT score equates to a successful medical career, and vice versa. Wrong!

To paraphrase one study2:
  • The writing sample and physical sciences sections carry no predictive value of med school performance.
  • Biological sciences and verbal reasoning scores positively correlate with MCCE part 1 scores.
  • Only verbal reasoning scores positively correlate with MCCE part 2 scores.
(The Medical Council of Canada Exams (MCCE) parts 1 and 2 are taken after completion of a medical degree; part 1 tests declarative knowledge & part 2 tests clinical reasoning.)
Now you know why many schools not only use the MCAT; but why many only look at verbal reasoning or verbal reasoning and biological sciences.

However, if you look at the actual numbers in this study2, the positive correlation and regression coefficients (albeit significant), describing the relationship between verbal reasoning and the MCCE parts 1 or 2 test scores, are not very convincing. Thus, the explained variance is not very satisfying either.

…But what do I know? I’m still wondering why I had to learn I.C.E. tables and answer questions on a short story about abstract art…

If divers are finding fish in sunken shipwrecks, does that mean fish are sinking ships?
As I indicated above, a high MCAT score does not necessarily mean you will be a good doctor (and vice versa). Clearly there are other factors which can be attributed to one’s success. For starters, the MCAT does not measure diligence, motivation and communication skills1.

Wait. Let’s back up here…
…What is a “good doctor?”
…Are the top academic medical students usually successful doctors?
…Are the bottom medical students less successful doctors?
…What are the cause and effect relationships between the MCAT, GPA, diverse extracurriculars and achievements throughout medical school and a medical career?

Herein lies the problem; what is a good or successful physician? I think the US Supreme Court answered this best when taking a stance on pornography: we know it when we see it, but any definition lacks concise parameters and is too subjective.

Long story short, the MCAT is a reputable achievement and aptitude test; albeit, it’s far from the end all to be all.  So, while we’re left with an imperfect system, I’m glad it’s an ever evolving system.

Chao,
Jeff

1. Prideaux D, Roberts C, Eva K, et al. Assessment for selection for the health care professions and specialty training: Consensus statement and recommendations from the Ottawa 2010 Conference. Medical Teacher, 2011, 33:215-23.
2. Donnon T, and Violato C. Does the Medical College Admission Test predict clinical reasoning skills? A longitudinal study employing the Medical Council of Canada clinical reasoning examination. Academic Medicine 2005, 80(10):S14-6.

No comments:

Post a Comment