Pick one school and stay there. That is the best advice. A lot of people transfer between the Caribbean schools, and this (especially) raises a lot of questions in the minds of residency program directors. For example, a lot of Ross students transferred to St. Matts some time back (after they couldn't hack it at Ross... sorry, not trying to sound harsh but it's true). I'm running into a few of these folks now in clerkships, and it's obvious why. However, I've also met some awesome St. Matt's students who really have their act together and are great doctors in training.
Long story short, the thing that matters most is the school's track record. If PD's have had a bad experience with a resident from a particular school, they're less likely to go back to that well in the future. One bad apple can truly spoil the barrel. But, if you start at St. Matts, plan on finishing there. Do your homework, though, and consider most strongly those schools who have a solid track record of getting their graduates into the residencies they want.
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