What's the general national average for Family Medicine shelfs?

metallo

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They always curve such that the average raw score is 70 with a SD of 8.
That's not true -- when the exam was developed, the first group had their scores standardized to a mean of 70 and standard deviation of 8. However, it isn't curved for each group that takes it. The average now is several points higher for most shelf exams. Depending on the time of year, for instance, the Internal Medicine averages can range from 73 in the first quarter of the year to 76 in the fourth quarter. I don't have the specific numbers for the Family Medicine shelf, but I think it's a safe bet that the averages now for all the shelf exams are closer to 75 than 70.
 

Dirt

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That's not true -- when the exam was developed, the first group had their scores standardized to a mean of 70 and standard deviation of 8. However, it isn't curved for each group that takes it. The average now is several points higher for most shelf exams. Depending on the time of year, for instance, the Internal Medicine averages can range from 73 in the first quarter of the year to 76 in the fourth quarter. I don't have the specific numbers for the Family Medicine shelf, but I think it's a safe bet that the averages now for all the shelf exams are closer to 75 than 70.
Do you work for the NBME? Because they clearly state that the test is scaled to a mean of 70 with SD of 8.
 

KnuxNole

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So what's the passing score for a shelf? Just wondering, when I take my first shelf I'm gonna aim for the stars, but just curious since I've never taken a clinical shelf before.

A bit off topic, but is it like the Pre-Step 1 shelves(125 questions)?
 

desijigga

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100 qs, and you get 2.5 hours.

For our school we need a raw score of >61 to pass. Each schools different though. Might want to ask your clerkship director, or look it up on your schools site for 3rd and 4th year stuff..
 

metallo

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Do you work for the NBME? Because they clearly state that the test is scaled to a mean of 70 with SD of 8.
Obviously I don't, because my sig clearly states that I'm a fourth year med student. Here's what the NBME says:

"The subject examination score is scaled to have a mean of 70 and a standard deviation of 8 for a group of approximately 10,000 first-time takers from 80+ schools who took the Medicine Subject Examination as a final clerkship exam following rotations during the 1993-94 academic year."

(taken from http://www.nbme.org/Students/SubExam/samplereports/medscoreint1.html)
 

ChiDO

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Here are the national means given to us by our school for last year. From my understanding, these national means are compromised of 3rd year medical students who have takek the test as their last 3rd year shelf (ie. have completed all rotations in 3rd year and prior shelf exams).

FM: 72.7
IM: 76.0
OB/GYN: 72.9
Peds: 75.8
Psych: 76.7
Surg: 72.4
 

McGillGrad

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This sounds like a faulty measure and probably high suspect, statistically. There aren't enough people taking each one last to compare.

This is probably only for your school since the NBME does not have the data to provide these results.

The NBME average is scaled to a 70.



Here are the national means given to us by our school for last year. From my understanding, these national means are compromised of 3rd year medical students who have takek the test as their last 3rd year shelf (ie. have completed all rotations in 3rd year and prior shelf exams).

FM: 72.7
IM: 76.0
OB/GYN: 72.9
Peds: 75.8
Psych: 76.7
Surg: 72.4
 

metallo

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This sounds like a faulty measure and probably high suspect, statistically. There aren't enough people taking each one last to compare.

This is probably only for your school since the NBME does not have the data to provide these results.

The NBME average is scaled to a 70.
Read the link in my last post -- the NBME does actually have this data, and I'm betting that ChiDO's numbers are right on. The average of 70 and standard deviation of 8 are for the original group that they used to curve the scores. It doesn't get rescaled for every group that takes the test.
 

McGillGrad

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Read the link in my last post -- the NBME does actually have this data, and I'm betting that ChiDO's numbers are right on. The average of 70 and standard deviation of 8 are for the original group that they used to curve the scores. It doesn't get rescaled for every group that takes the test.
You are misreading the NBME information.

Just as they use old data to calculate your score on their Comprehensive examinations (Comprehensive Basic Science Self-Assessment (CBSSA)), which they compare to a similar cohort from the 1990s, they use the same formula to compare you to a group taking the shelfs.

How in the world does the NBME know what order each student takes his/her 3rd year rotations? It is different for almost every student, and varies between med schools.

The scores that ChiDo quotes are for people who took each shelf exam at the end of his/her one last in 3rd year. So, even within a class, it will vary from person to person.

Can you see what I mean?
 

metallo

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You are misreading the NBME information.

Just as they use old data to calculate your score on their Comprehensive examinations (Comprehensive Basic Science Self-Assessment (CBSSA)), which they compare to a similar cohort from the 1990s, they use the same formula to compare you to a group taking the shelfs.
Correct -- I believe we agree on this point, although I'm not misreading anything.

How in the world does the NBME know what order each student takes his/her 3rd year rotations? It is different for almost every student, and varies between med schools.
They don't know the order, but I never claimed that they do. The NBME does, however, know the quarter of the year during which you took the test, since they know the date you took the exam when they score it. To create their list of data, they look at the average score for everyone taking it during the first quarter, second quarter, etc. Providing that list to clerkship directors allows them to set different minimum scores for honors, high pass, passing, etc. based on how far each student is into third year, but not based on which clerkships they have already taken.

The scores that ChiDo quotes are for people who took each shelf exam at the end of his/her one last in 3rd year. So, even within a class, it will vary from person to person.
You said ChiDO's numbers are just for his (or her) class only -- I highly doubt that. I'm guessing those are the fourth quarter (end of year) numbers published by the NBME for each shelf exam.

Can you see what I mean?
Apparently not. You said that the NBME average is scaled to 70 -- currently, that's not true. It was scaled to 70 for a group back in the 1990s, but it is not scaled for each group that takes the exam now and therefore has increased for all of the shelf exams.
 

McGillGrad

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You said ChiDO's numbers are just for his (or her) class only -- I highly doubt that. I'm guessing those are the fourth quarter (end of year) numbers published by the NBME for each shelf exam.
You should really reread his post. He specifically stated that each average was based only on people who took that shelf exam as their last core shelf.



Apparently not. You said that the NBME average is scaled to 70 -- currently, that's not true. It was scaled to 70 for a group back in the 1990s, but it is not scaled for each group that takes the exam now and therefore has increased for all of the shelf exams.
You seem to be proving my point..then suddenly creating imaginary data that is never stated on the NBME web site. There is nothing published by the NBME that states anything other than scaling the score to 70.
 

metallo

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You should really reread his post. He specifically stated that each average was based only on people who took that shelf exam as their last core shelf.





You seem to be proving my point..then suddenly creating imaginary data that is never stated on the NBME web site. There is nothing published by the NBME that states anything other than scaling the score to 70.
OK, I think you misunderstood what I was trying to say. I agree that the *NBME* has only scaled the exam to 70, and I never stated otherwise. However, it was scaled over a decade ago. My point was that they don't rescale it. Therefore, the average has increased -- note that I'm not talking about the scaled NBME average changing (that's still 70). I mean the actual average for the cohort of students in a particular year (or quarter of a year). Lately, those numbers have tended to be several points above 70, and I believe that's what the OP was asking about -- not the original scaled average, but the current average, which is not determined solely by the NBME's arbitrary curving, but by actual recent examinee performance.

As for ChiDO's post, yes, he did state that it was for people taking it as their last shelf. I bet his numbers are right, but they're probably the fourth quarter results published by the NBME, since as you pointed out, the NBME doesn't know the order of each student's rotations.
 
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For the last shelf given at my school:

In Peds 85 raw was 88th
In Family 85 raw was 95th

God only knows how the hell raw scores and percentiles are calculated.