Residency programs don't care a whit about your MCAT scores. What they care about are the following:
(1) Are you a liability? Essentially, no program wants a problem resident. You prove that you are not going to be a problem with no hiccups during your education (meaning that you sailed through your program without being held back), your letters of recommendation (which are vouchers from trusted people that you are an upstanding person), and a solid track record of prior accomplishment with no personal blemishes (you haven't been arrested or convicted of anything, etc.). This, in essence, tells the program that you are low risk if they offer you a spot.
(2) Will you pass the boards on your first try? You demonstrate this by high board scores. You may be the smartest person in the world, but if you have trouble with standardized tests you might struggle when it comes time to sit for board certification.
(3) Are you dependable? Again, much like item (1), this is a bit harder to prove. Getting into a residency is a bit like marrying someone after a first date. They want to see such intangible things like how your appearance looks during the interview (which shows that you care about how you present yourself), whether or not you misspelled words in your personal statement, if you show up on time and look interested, if you ask relevant questions and are engaging, and whether or not you appear serious about your profession. Some of these things are subtle, but they can definitely come across in the interview - which is why we have interviews.
(4) Are you motivated? Ironically, proving that you earnestly want to be a physician by going through the trouble of inserting yourself into a foreign country for a few years, moving around to do clinicals, and getting through the program without delay actually helps you in this regard. Of course, some residency programs will not even consider you because of a Caribbean degree, others see this as a huge plus. But, you have to do your part too by not having any major mistakes during your time obtaining your degree.
MCATs have no bearing on any of these things, and they're not even asked for during the residency application process.
Good luck!
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PGY-4/CA-3
Graduate with Honors, Ross University (2005)