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Your oldest thread
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forums.studentdoctor.net
If my calculations are correct you have only taken 15 hours of postbac coursework (great job with the A's). What courses did you take?
Swallow your pride and apply DO unless you love to take the chance at another failed cycle. You don't need to retake the MCAT, and taking it a third time won't really help you since many schools average MCAT attempts for screening (so you're at 511). If you can do better than 521, then go for it, knowing that you should treat your MCAT average as the calling card to your application.
Give me your reason why a school should interview you this summer/fall. You talk about future plans to get you to that reason, and that will only motivate some schools to push your application to the "wait until next year" pile.