It would be interesting to see how MCAT score correlates with USMLE score. Wondering if there's a stronger correlation there than between MCAT score and med school GPA.
It does. A couple of people have pointed it out already, I suspect. If you google MCAT step I correlation, you'll find a couple of relevant studies. There are also a couple of score estimators that use compiled MCAT data for prediction.
Drawing meaning from the aggregate data about MCAT scores/Step I/match rates, is where it is easy to kid yourself, particularly if you are not familiar with the multiple intricacies of this system, such as the very important difference between matching in categorical or prelim position which was noted above.
Generally speaking, a person who struggles to get a 24 on the MCAT (the old MCAT, I have no idea how the new one is even scored) after multiple attempts, will have difficulty passing or performing in a confidence inspiring manner on Step I. This is a huge obstacle to matching, especially for an offshore student. From the data, it would seem that a significant amount of offshore students fit in this category. On the other hand, there have been plenty of examples of people with a decent GPA, marginal MCAT say 27-28, who went to Carib schools, applied themselves, performed adequately, matched into relatively non-competitive primary care residencies, and owing to the favorable rural primary care job market, are gainfully employed, able to pay off debt, and are having nice lives.
So although these two examples may fit in the same data spread of matriculated students, what they can mean for an individual is substantially different.
It's my opinion that the business model of many of these medical schools seems to depend on not making this distinction very clear, which seems kind of unethical. While we no longer live in the England of Charles Dickens, where people on the losing end of this exchange were relegated to debtor's prison or the workhouse, paying off debt of this magnitude can put financial stress on families for generations.
So, to the OP, depending on how deep in the hole you are, it would be wise stay the course, work incredibly hard, look for residencies that are not competitive, and make yourself appear to be hard working, reliable, knowledgeable, and as low risk to a PD as you can be. Sometimes you find yourself in a bad fix, and your best option is to keep your head down in the trenches, and steadily dig your way out. If you are early on, at least researching options other people discussed like going to Anesthesiology Assistant school or Path assistant school (depending on interests) are pretty reasonable.
Best of luck.
Sadly, there are likely people who scored in the 20s in my class doing much better than I am. 
