Is there a correlation between doing well/poorly in premed classes and the mcat?

[alexfoleyc]

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I justed wanted to know if doing poorly in a one of the premed classes would affect mcat performance. Maybe those who have taken the official mcat can share their scores and science gpas, and we can attempt to find a correlation.

 

[Shinobiz11]

Well, I would say because pre-med pre-requesites are suppose to teach you the fundamentals that you will learn in medical school and the MCAT is used to weed out non-potential pre-med's from the crowd. then yes. If the MCAT is based on such topics like english, biology, chem, physics, writing, then it is obviously directly related to what you learned in your pre-med classes.
Still have four years until I take the MCAT, maybe I can get back to you on this. 🙂

 

[45408]

Probably. You need to know the material quite well.

 

[oaklandguy]

You'll only be helping yourself to be successful in your pre-requisite classes. Just because you do poorly does not mean that you will not succeed on the MCAT. Many current SDNers have done pretty poorly in some of the prerequisites and still managed 35+'s and even some 40+'s. The MCAT is one big test that you can study for. It would be hard to learn all the material in a short amount of time studying for the MCAT, but remember the core science classes only make up for 2/3 of the MCAT anyways.

 

[MilkmanAl]

2.9/35. Hmmm... *watches the thread explode*

I'd imagine there's probably a very weak correlation if any. Not all 4.0's were created equal.

 

[just one]

I justed wanted to know if doing poorly in a one of the premed classes would affect mcat performance. Maybe those who have taken the official mcat can share their scores and science gpas, and we can attempt to find a correlation.

There are people with 4.0 GPA and score low on MCAT, and people that have 3.0 and score extremely well. The question is how hard did people work on their GPA, some only squeak by and prepare hard for the MCAT and vice versa. Since I was a returning student battling a low GPA from ten years prior, I focused extremely hard on classes. With a wife, child, full time job, full time class load, when do I have the time to put in 5 hours a day like some traditional students? My MCAT was not what I think it could have been if I gave it a solid effort instead of a couple weeks for an hour or two after I put my kid to bed between semesters. But thats life, I was accepted and don't need to worry about it.

One class does not predict MCAT greatness/failure, yet if struggling in all science prereqs while putting forth tremendous effort occurs, it is not a good sign.

Geez, I just posted quite a bit of common sense huh? Stop worrying about one class and move on

 

[Global Warming]

Correlation? Yes

Causation? No

 

[ziggydoc]

Well, it really depends, like everyone said, it is very different studying for the MCAT and maintaining a good GPA. In general, the idea is what you study in your pre-reqs will be tested on the MCAT, but then again, you can have bad luck/professors/class or whatever that tanks your GPA but you still learned the material very well and score awesome on the MCAT, or you can be like me... Maintain a good GPA and don't do awesome on the MCAT.

 

[jvesco22]

2.9/35. Hmmm... *watches the thread explode*

I'd imagine there's probably a very weak correlation if any. Not all 4.0's were created equal.

Your single personal example wouldn't have any effect on the correlation. Why would you think it's very weak? Makes no sense.

 

[RogueUnicorn]

guys the aamc probably has data on this if someone cares enough to check.

 

[Uisa]

You know, I've been wondering about this too. I personally do not have a great GPA to boast about, but my school is known for grade deflation... on the other hand, there are those with like 3.9 at the school who in the past have gotten in to the top 3 med schools.

Just goes to show that not all GPA is created equal and that MCAT is definitely something that can "defy" what your GPA says about you.

Then again, as previously mentioned by others, that sub-par grade you received in your institutions pre med courses, better be from a huge commitment and not from a lack of studying.

 

[MilkmanAl]

Your single personal example wouldn't have any effect on the correlation.

*sigh*

Why would you think it's very weak? Makes no sense.

It makes perfect sense if you consider that there is a hell of a lot more variability in MCAT scores than GPA amongst applicants and that, as I said, GPA's aren't particularly equivalent across the board.

 

[Trogghunter]

The MCAT really shouldnt have so much weight on it.
I put a moderate amount of work into maintaining a 3.9 gpa with bio, chem, and french concentrations...and ive taken 5-7 classes consistently per semester and i do many hours of research in a molecular bio lab per week(with a first author publication, another one on the way), along with hundreds of hours of volunteering, shadowing, community service/executive position in my fraternity, etc. Anyway, i didnt really study for the MCAT for longer than a month, and it shows since i got a 27S...which was weird because I scored +/-35 on the practice tests that i took. no way in hell that im taking it again...ive already been accepted, but i really dont think that the MCAT is so important for every school as long as a candidate is well rounded and has great letters, and is obviously mature(although i just turned 21). i got rejected from a couple of schools for it...but if they want to penalize me for a lack of effort on a stupid test, then it's their loss. anyone else feel this way?

 

[RogueUnicorn]

The MCAT really shouldnt have so much weight on it.
I put a moderate amount of work into maintaining a 3.9 gpa with bio, chem, and french concentrations...and ive taken 5-7 classes consistently per semester and i do many hours of research in a molecular bio lab per week(with a first author publication, another one on the way), along with hundreds of hours of volunteering, shadowing, community service/executive position in my fraternity, etc. Anyway, i didnt really study for the MCAT for longer than a month, and it shows since i got a 27S...which was weird because I scored +/-35 on the practice tests that i took. no way in hell that im taking it again...ive already been accepted, but i really dont think that the MCAT is so important for every school as long as a candidate is well rounded and has great letters, and is obviously mature(although i just turned 21). i got rejected from a couple of schools for it...but if they want to penalize me for a lack of effort on a stupid test, then it's their loss. anyone else feel this way?

i feel the same way about gpa. it's really just a matter of perspective. you root for the home team.

 

[Toadesque]

The MCAT really shouldnt have so much weight on it.
I put a moderate amount of work into maintaining a 3.9 gpa with bio, chem, and french concentrations...and ive taken 5-7 classes consistently per semester and i do many hours of research in a molecular bio lab per week(with a first author publication, another one on the way), along with hundreds of hours of volunteering, shadowing, community service/executive position in my fraternity, etc. Anyway, i didnt really study for the MCAT for longer than a month, and it shows since i got a 27S...which was weird because I scored +/-35 on the practice tests that i took. no way in hell that im taking it again...ive already been accepted, but i really dont think that the MCAT is so important for every school as long as a candidate is well rounded and has great letters, and is obviously mature(although i just turned 21). i got rejected from a couple of schools for it...but if they want to penalize me for a lack of effort on a stupid test, then it's their loss. anyone else feel this way?

well...you would have the exact opposite opinion if you got a 35 on the MCAT but had a 3.0 GPA, wouldn't you say?

 

[coldweatherblue]

well if it makes you feel better I didn't do well in my science classes (3.4 GPA) and was really happy with the MCAT (+2 SD).

but I paid... oh how i paid having to re-learn Bio and G-chem in the months before the MCAT. freaking sucked.

Learn it right the first time and everything will come easier. I know it's easier said than done but it's the best way.

The earlier you train yourself to put in the hours needed to succeed, no matter how many hours it may take, the better you'll be prepared for the rest of your education.

 

[dingyibvs]

The MCAT really shouldnt have so much weight on it.
I put a moderate amount of work into maintaining a 3.9 gpa with bio, chem, and french concentrations...and ive taken 5-7 classes consistently per semester and i do many hours of research in a molecular bio lab per week(with a first author publication, another one on the way), along with hundreds of hours of volunteering, shadowing, community service/executive position in my fraternity, etc. Anyway, i didnt really study for the MCAT for longer than a month, and it shows since i got a 27S...which was weird because I scored +/-35 on the practice tests that i took. no way in hell that im taking it again...ive already been accepted, but i really dont think that the MCAT is so important for every school as long as a candidate is well rounded and has great letters, and is obviously mature(although i just turned 21). i got rejected from a couple of schools for it...but if they want to penalize me for a lack of effort on a stupid test, then it's their loss. anyone else feel this way?

I think I echo others' sentiment on here I didn't study for more than a month for the MCAT either, but I did get a 4.0 on my pre-reqs as well.

 

[vin5cent0]

I'm sure there's a slight correlation between the two, but one doesn't cause the other.

Grades are very inconsistent. We have two orgo teachers at my school. One counts a B as 65-85%, A 85-100%. The other is 90-100% A, 70-80% B, etc etc. You can see how it could make two equal performers in the class get different grades for no reason other than having different teachers.

MCAT, on the other hand, is (I'm hoping) much more standardized. Not only that, but GPA isn't a very good factor for intelligence (of course I say that with my sub-3.5 GPA). I have a friend who is a 4.0 Chem major, but ALL she does is study study study. If she gets a point off on a test, she argues it for all she can to get it back. I, on the other hand, accept points off on a test and like to have more of a social life than library life. That said, I feel like I'm probably smarter than her as I often have to explain things to her and whatnot. The GPA certainly doesn't tell all..

 

[vin5cent0]

The MCAT really shouldnt have so much weight on it.
I put a moderate amount of work into maintaining a 3.9 gpa with bio, chem, and french concentrations...and ive taken 5-7 classes consistently per semester and i do many hours of research in a molecular bio lab per week(with a first author publication, another one on the way), along with hundreds of hours of volunteering, shadowing, community service/executive position in my fraternity, etc. Anyway, i didnt really study for the MCAT for longer than a month, and it shows since i got a 27S...which was weird because I scored +/-35 on the practice tests that i took. no way in hell that im taking it again...ive already been accepted, but i really dont think that the MCAT is so important for every school as long as a candidate is well rounded and has great letters, and is obviously mature(although i just turned 21). i got rejected from a couple of schools for it...but if they want to penalize me for a lack of effort on a stupid test, then it's their loss. anyone else feel this way?

I don't. I think your MCAT performance shows more than your GPA. Your GPA may show that your intelligent.. or it may show that you're an average student who studies a lot. No harm in that, of course. However, the MCAT is a good way to determine someone's intellect at solving problems in a timed manner.

 

[Insulinshock]

Look at this way: An above average person can score a cumulative GPA of 3.85 if they put a bunch of effort in and demand perfection of themselves.

That same person could easily get a 3.25 if they didn't study as much as they needed to and went out on the weekends when they should have been preparing for the Monday morning test.

I would think that there is a weak correlation simply because, as others said, getting good grades in pre-reqs means that you're learning the material, which will give you an advantage come test time. However, I would assume this correlation would be no more than two points or so + or - on the test.

 

[tradgirl]

Not all 4.0's were created equal.

^What Al said.

I'm sure there is a strong correlation, because your performance on the MCAT is directly related to your knowledge of the material, which is at least somewhat related to your performance in the core courses.

That said, I thought I had a very firm grasp of the material in my pre-med classes, but they were graded on a harsh curve, and I didn't take the extra time to memorize every inane detail in each subject or labor fruitlessly for extra hours on every assignment. I came out with ~3.3 sGPA. My MCAT is >95%ile.

Don't worry about it if your grades aren't "up to snuff" -- just make sure your knowledge is.

 

[dru2002]

Well it depends. The article is from 1983 so it is a little dated but is still probably pretty valid.

A biology score of 9.28 correlates to a 2.31-3.00 GPA at the most selective universities. At mediumly selective universities a 9.16 correlates to a 3.61-3.80 GPA. And at the least selective an 8.87 correlated to a 3.81-4.0 GPA.

Source:
Jones, R. F. & Adams, L. N. (1983). The Relationship between MCAT Science Scores and Undergraduate Science GPA. Journal of Medical Education, 58, 908-1011.

 

[boaz]

I would imagine that there is a correlation in the sense that if the prereqs don't go well (assuming hard work), the MCAT probably won't go well either. But the inverse is not true: we've heard plenty of stories of people with 3.9-4.0 who scored poorly on the MCAT.

 

[deleted74029]

2.9/35. Hmmm... *watches the thread explode*

I'd imagine there's probably a very weak correlation if any. Not all 4.0's were created equal.

This.

I was barely scraping the 3.0 surface and had the same MCAT as a girl at my undergrad with a 4.0 (was a pretty average score nonetheless), difference though was that she got an acceptance in the mail whereas I got rejections.

 

[Optimalsauce]

guys the aamc probably has data on this if someone cares enough to check.

AAMC does, you can turn the grid into a scatter plot for the past 3 years although it's not perfect due to ranges and not specific GPAs and MCAT.

 

[caseofthemndays]

3.2/34 MCAT tests a different way of thinking than most sciences classes I took...

 

[wanderer]

AAMC does, you can turn the grid into a scatter plot for the past 3 years although it's not perfect due to ranges and not specific GPAs and MCAT.

Doesn't this assume that everyone who takes the MCAT applies?

 

[kansaskid]

So I haven't read the whole thread, but I just wanted to say that after taking practice MCATs I can definitely say that there is not much correlation between grades and MCAT score (before MCAT studying that is). My first practice physical sciences section was horrifically bad and I made easy As in physics. I think that a good foundation is important, but mostly what a good MCAT score is a reflection on is how well you studied for the MCAT.

 

[Spiker]

Of course there is correlation. If you plot them in a graph there will be a linear relationship. However, if one causes another is unknown (but we can probably guess...for example: people with high gpa are better students and usually study some what harder than a 3.0 student or getting 4.0 shows that you learned alot of stuff on MCAT well). Of course you can get a 40 MCAT with 3.0 GPA but The fact is most people with 40 got a GPA pretty damn close to 4.0 and those with 4.0 GPA rarely get a 20 on MCAT.

 

[slowbutsteady]

If you do poorly in pre-reqs, here's a hint: Don't bother taking the MCAT. You aren't getting into med school.

 

[elementals]

I got a 41T, and my undergrad science GPA was a 3.42. Course, I will admit it was a 3.42 because I skipped classes all the time and didn't study until 24hrs before the exams, LOL. I will also admit I had to work my ass off for a 41, and I only worked that hard because I knew I had to offset the GPA somehow.

So... yeah, there is a correlation in my case? But it's sort of a deliberate, conscious correlation, if that makes sense.

 

[RogueUnicorn]

If you do poorly in pre-reqs, here's a hint: Don't bother taking the MCAT. You aren't getting into med school.

lolwut

Of course there is correlation. If you plot them in a graph there will be a linear relationship. However, if one causes another is unknown (but we can probably guess...for example: people with high gpa are better students and usually study some what harder than a 3.0 student or getting 4.0 shows that you learned alot of stuff on MCAT well). Of course you can get a 40 MCAT with 3.0 GPA but The fact is most people with 40 got a GPA pretty damn close to 4.0 and those with 4.0 GPA rarely get a 20 on MCAT.

you know this how?

 

[Spiker]

you know this how?

From all 4.0 that I know in my school (actually none of them even have sub 30). And all the 39+ in my school for past 3 years (everyone know who they are) have gpa of 3.8+. Of course that is a generalized statement with no scientific proof.

Are you really seriously doubting the validity of the statement that people with extrmemely high GPA dont usually do extremely poorly on MCAT. And people with 40+ MCAT usually have pretty high GPA?

I am just saying there is pretty strong correlation (my premedical adivisor actually tracked this over last 15 years and we have over 200 premed each year (about 100+ gets in) she doesnt release the stats but let us know there is a extremely high correlation between the two stats.) but for multiple reasons some of which I already stated.

 

[Spiker]

http://www.aamc.org/data/facts/applicantmatriculant/table24-mcatgpa-grid-3yrs-app-accpt.htm

Look at the data here and assume that most people with 3.5+ and 30+ GPA/MCAT going to apply and look at the trend from there it is not a hard one to tell.

 

[RogueUnicorn]

applicants =! overall pool

 

[RogueUnicorn]

From all 4.0 that I know in my school (actually none of them even have sub 30). And all the 39+ in my school for past 3 years (everyone know who they are) have gpa of 3.8+. Of course that is a generalized statement with no scientific proof.

Are you really seriously doubting the validity of the statement that people with extrmemely high GPA dont usually do extremely poorly on MCAT. And people with 40+ MCAT usually have pretty high GPA?

I am just saying there is pretty strong correlation (my premedical adivisor actually tracked this over last 15 years and we have over 200 premed each year (about 100+ gets in) she doesnt release the stats but let us know there is a extremely high correlation between the two stats.) but for multiple reasons some of which I already stated.

i am just saying you can't say this unless you show me the actual stats and regressions.

 

[Spiker]

i am just saying you can't say this unless you show me the actual stats and regressions.

Of course I can say this lol I am not submitting it to a scientific journal. If you really want one you can search GPA and MCAT (http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2625543/) done on a black population there is a correlation of about 0.5. Which is pretty significant.

Most people wont have a hard time believing what i said. If you dont believe anything another person say without scientific proof/paper cited how do you even talk to other people??

 

[Spiker]

applicants =! overall pool

I know and I told you to make assumptions. Even in Scientific experiments you are some times force to make assumption.

 

[RogueUnicorn]

Of course I can say this lol I am not submitting it to a scientific journal. If you really want one you can search GPA and MCAT (3rd in google search) done on a black population there is a correlation of about 0.5.

Most people wont have a hard time believing what i said.

uh, this study you're mentioning, http://journals.lww.com/academicmed...cademic_performance_at_a_predominantly.1.aspx

is from 1986. also, the study correlates uGPA and MCAT with med school GPA, so it's not even what you're looking for.

 

[RogueUnicorn]

I know and I told you to make assumptions. Even in Scientific experiments you are some times force to make assumption.

and i'm challenging this terrible assumption. using the FACTS table here is very misleading; in the same sort of reasoning you're using i can say that it's twice as likely to get a 4.0 (23 850 applicants) than it is to get a 3.0 (11,105)

 

[Spiker]

Go refresh I gave you the link of the article.

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2625543/

"Correlation coefficients for a number of available independent variables with MCAT scores were determined for a population of premedical students at Xavier University of Louisiana. American College Testing (ACT) and Scholastic Aptitude Test (SAT) scores were found to have similar ability to predict MCAT scores, with a correlation coefficient of 0.64 between ACT composite and MCAT total scores. Correlations of sophomore year grade point average (GPA) with MCAT scores were only slightly weaker."

 

[RogueUnicorn]

Go refresh I gave you the link of the article.

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2625543/

"Correlation coefficients for a number of available independent variables with MCAT scores were determined for a population of premedical students at Xavier University of Louisiana. American College Testing (ACT) and Scholastic Aptitude Test (SAT) scores were found to have similar ability to predict MCAT scores, with a correlation coefficient of 0.64 between ACT composite and MCAT total scores. Correlations of sophomore year grade point average (GPA) with MCAT scores were only slightly weaker."

this is from 1987

Most people wont have a hard time believing what i said. If you dont believe anything another person say without scientific proof/paper cited how do you even talk to other people??

we are not having a casual conversation right now. you're bandying about terms like strong correlation, for which you need to cite evidence.

 

[Spiker]

Despite how old that paper is, that and the AMCAS data should be able to convince most people. If you dont think that is strong enough evidence then oh well. Plus coorelation is easy to establish unless you really think that a 1.0, 2.0, 3.0 and a 4.0 have exactly same chance of getting a 40 on MCAT then there will be correlation.

 

[Spiker]

and i'm challenging this terrible assumption. using the FACTS table here is very misleading; in the same sort of reasoning you're using i can say that it's twice as likely to get a 4.0 (23 850 applicants) than it is to get a 3.0 (11,105)

It is not as misleading as you think..

Do it by percentage...

Add up all the 4.0 and see what % get 40

Add up all the 3.0 and see what % get 40

 

[Spiker]

So here is something I just calculated:

I used Application Row for 3.40-3.59 and 3.80-4.00

I summed up all the ones scoring above 30 on MCAT

Those two are the most accurate critia because most of the people with that kind of stats are going to apply

Figuring out the percentage for each..

3.80-4.00

42% (30-32) 32% (33-35) 18% (36-38) 7% (39-45)

3.40-3.59
58% (30-32) 30% (33-35) 10% (36-38) 2% (39-45)

As you can see lower gpa= a shift to lower score

 

[RogueUnicorn]

Despite how old that paper is, that and the AMCAS data should be able to convince most people. If you dont think that is strong enough evidence then oh well. Plus coorelation is easy to establish unless you really think that a 1.0, 2.0, 3.0 and a 4.0 have exactly same chance of getting a 40 on MCAT then there will be correlation.

considering at the writing of the paper the MCAT was completely different test, and that this study was based in one atypical university, i would have to argue that the age is quite relevant here. also, i've already stated why the FACTS table is not a proper source for this discussion, given its extreme skew; you have yet to assert why it's ok to use it. as a final point, you keep bringing up "most people." i don't even see what "most people" entails in particular or why it should matter; if you are making a sound argument, you are making a sound arguemnt. if you aren't, then you aren't. if you're in some way suggesting that i'm forcing some sort of extreme, unreasonable viewpoint on you, then i would have to a) disagree and b) ask you to show why that is. in any case this appeal to a phantom audience should be dropped.

 

[Spiker]

considering at the writing of the paper the MCAT was completely different test, and that this study was based in one atypical university, i would have to argue that the age is quite relevant here. also, i've already stated why the FACTS table is not a proper source for this discussion, given its extreme skew; you have yet to assert why it's ok to use it. as a final point, you keep bringing up "most people." i don't even see what "most people" entails in particular or why it should matter; if you are making a sound argument, you are making a sound arguemnt. if you aren't, then you aren't. if you're in some way suggesting that i'm forcing some sort of extreme, unreasonable viewpoint on you, then i would have to a) disagree and b) ask you to show why that is. in any case this appeal to a phantom audience should be dropped.

I did address you objection to FACTS table. First by taking percentage rather than obsolute number. Second by only taking into account of those who have high enough stats to apply (so applicant pool is as close to those population pool as possible)

Regarding the article despite the new version of MCAT the content or distribution have not changed significantly.

Again, I am not saying this is good enough to publish, but it is not just mere opinion either. I dont think you should hold this forum to the level of standard.

And, the reason that "most people" matter is because those are the people I am trying to inform. You? not so much

On average do people with 1.0, 2.0, 3.0 and a 4.0 have exactly same chance of getting a 40 on MCAT?
If you answer is no, then there will be correlation.

Simple as that Correlation is not Relation and it isnt that difficult to establish.

 

[RogueUnicorn]

I did address you objection to FACTS table. First by taking percentage rather than obsolute number. Second by only taking into account of those who have high enough stats to apply (so applicant pool is as close to those population pool as possible)

Regarding the article despite the new version of MCAT the content or distribution have not changed significantly.

Again, I am not saying this is good enough to publish, but it is not just mere opinion either. I dont think you should hold this forum to the level of standard.

And, the reason that "most people" matter is because those are the people I am trying to inform. You? not so much

On average do people with 1.0, 2.0, 3.0 and a 4.0 have exactly same chance of getting a 40 on MCAT?
If you answer is no, then there will be correlation.

Simple as that Correlation is not Relation and it isnt that difficult to establish.

correlation IS relation. it is not causation.

the MCAT from back then and now is SUBSTANTIALLY different. look up the history. the percentages are also obfuscating what is acutally happening, again due to massive sampling issues. how does this account for people whose gpa changes between mcat administration and application? it doesn't. i'm holding you to the standard expected of anyone asked to prove anything. you are not meeting it and are implicitly admitting it's not possible to do so. a final point about your arguments - i never questioned correlation, i challenged your statement that "The fact is most people with 40 got a GPA pretty damn close to 4.0 and those with 4.0 GPA rarely get a 20 on MCAT." which you've since turned into a correlation debate.

and while we're at it, a small exercise in stats - let's assume there's a moderate-low correlation between uGPA and MCAT, which i would believe (key point- believe, NOT know) there is. a ballpark "moderate" correlation coefficient r is ~0.4. with an r of 0.4, with a std dev of ~6 on the MCAT, GPA accounts for about a point on the MCAT.

 

[ilikekiwis]

lol why do you people care so much?

OP, put in enough work in your classes, you'll get a decent gpa; put in enough work on the mcat, you'll likely end up with a decent score.

worry about wat you can do and not wat others have done

 

[Spiker]

correlation IS relation. it is not causation.

the MCAT from back then and now is SUBSTANTIALLY different. look up the history. the percentages are also obfuscating what is acutally happening, again due to massive sampling issues. how does this account for people whose gpa changes between mcat administration and application? it doesn't. i'm holding you to the standard expected of anyone asked to prove anything. you are not meeting it and are implicitly admitting it's not possible to do so. a final point about your arguments - i never questioned correlation, i challenged your statement that "The fact is most people with 40 got a GPA pretty damn close to 4.0 and those with 4.0 GPA rarely get a 20 on MCAT." which you've since turned into a correlation debate.

and while we're at it, a small exercise in stats - let's assume there's a moderate-low correlation between uGPA and MCAT, which i would believe (key point- believe, NOT know) there is. a ballpark "moderate" correlation coefficient r is ~0.4. with an r of 0.4, with a std dev of ~6 on the MCAT, GPA accounts for about a point on the MCAT.

Clearly I dont have the data to provide the level of certainty you want. I will let others judge if what I said is useful. And if GPA and MCAT are correlated. Correlation statement is one that I try to establish the whole time. and "The fact is most people with 40 got a GPA pretty damn close to 4.0 and those with 4.0 GPA rarely get a 20 on MCAT." is just a dumbed down example?