The rankings themselves are pretty meaningless. They are composed of factors that really don't affect you in med school, and certainly don't tell you which school is "better" in any useful measure. People on here use the research ranking, a ranking basically based on how much NIH funding a program gets, because it is a loose proxy for "prestige". The more prestigious places are the ones with more groundbreaking reasearch going on, and hence more grants. You can go into research from any program -- it's not so much that the ones higher on this list are better for that, although research opportunities as a med student might be more plentiful at a better funded program, so if you are bent on research then sure the programs ranked 50-60 or higher might give you an edge on setting that up (although it's still not fatal, you can always spend your first year summer going elsewhere to do research). So no, it's not even a measure of which programs are "better" for research, it's a measure of funding which is a proxy for prestige. The primary care rankings aren't useful for anything. These rankings are based primarily on how many people go into primary care. So as a result, some DO schools find their way toward the top and some of the more prestigious programs on the research ranking list find themselves deeper in the list. But there is never an impediment to going into primary care from a research heavy school. Many people do. There is no suggestion that the primary care ranked schools do a better job at preparing their students for primary care, just that more go into it. And since many primary care fields are less competitive, it's hard to parse out who actually came out of these programs wanting primary care, and who defaulted into it.
So in short, you can use the research ranking as a very very loose gauge of prestige, and can't use the primary care ranking for anything of value. I wouldn't look at schools ranked #1 or, say, #35 and expect any major difference in med school experience, any major difference in residency opportunities, etc. There are only 125 or so US allo med schools, each with fairly small classes averaging about 150 people. Over half of all applicants to allo med school won't get in, and that is already a very self selecting group based on grades and MCAT scores, so the are all very very competitive and classes at all will be very very credentialed and solid. It's kind of silly to try to rank which is better/worse based largely on non-school related factors. So sure, use the research ranking loosely -- not to think the program ranked #1 is better than #5 or #25, or that you will be a better doctor, or will have better job expectancy, but to give you a loose sense of prestige. And that's pretty much it. Where you think you will work hard and will thrive and do well is more important than the rank. Someplace with nice infrastructure, good IT resources, a good library beats rank any day.
