How is Step 1 scored?

[richykav]

OK, so I'd like some opinions as to how people think USMLE Step 1 is scored as I have a theory and I was wondering what other people think. I've heard of the whole 1 mark per question thing but I don't think that this could possibly be a fair way of marking an exam of just 350 (or 300) questions taken from a bank of thousands. What I mean is that how can this way of marking an exam make scores comparable from person to person if everybody gets a different set of questions?

So, my theory is that you are marked on a curve based on the performance of other students who answered the same questions, i.e. if you take the average number of students who answered the question correctly and then average this over the whole 350 (or 300) questions and then compare this to the percentage of questions that you got correct, this is how your score is calculated. This would be based on an average score of 215, so if you got the same percentage of questions correct as all other test-takers then you are given a score of 215, if you get a better percentage you score higher and a worse percentage you get lower.

To me this seems the only way that scores can be standardised from person-to-person and from year-to-year, and it also would explain the need for 'experimental questions' as these would need to be answered by a large number of students to allow calculation of the average 'score' for each particular question before they were included in the actual exam.

I would appreciate your thoughts and opinions on this theory, or even better if anyone knows the actual scoring system it would be great to hear from you. Thanks.

[usmlelover]

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