I am currently a fourth year student that transferred following my second year. I transferred because I took 2 years off after my second year to pursue research in another city. The research was going really well and I wanted to be nearby to continue the research, albeit at a limited level. Thus I transferred from my old school, not ranked in US news, to my current school, a top 20 school.
What I've heard about transferring is that if a school allows it, it usually only allows it between the second and third years. Which makes sense in terms of continuity. As mentioned above, the best reason / most valid in the eyes of the school is a family issue. My current school made it clear that those people receive first priority. I have met the other transfers in my class that transferred with me. 2 of the 3 had family issues, the last one had a boyfriend starting his residency and asked the chairman of his department make some calls. He happens to be a nice guy, did it, and it worked. I guess thats another way transfer. But the trend is that family / future family? is the way to go.
So obviously, I found out later that I was the late one to be offered a spot. It was not easy. Not so much in that I had a lot to fill out. All my school wanted was a letter stating the reason. they never asked for grades, mcats, etc. It was just a matter of priority for the other transfers, and then waiting for a spot to open up. At the last minute someone in my current class was taking time off or something, and therefore I got a call a month before classes started to join the class. My advantage was that I worked at a nearby medical center to my school and my PI made a few calls and word got around somehow to the higher ups and I'm sure that helped.
My old school's student advisor once showed me a list of schools and whether they take transfer students, how many they take, and what year level they take them in. THat may be something to look into.
hope this helps
