The most obvious is knowledge. I've drunk from the proverbial "firehose" of information that we experience in medical school, and apparently enough of the facts stuck with me to pass all my exams, and secure myself a residency program back in my homestate of California. I was blessed enough to match last month into a 5 year program, at the end of which I'll be board certified in both family medicine and psychiatry. Significantly different from the pediatrician I thought I was going to be when I started med school, but at least I stuck (mostly) with primary care!
The change in specialty shows another way medical school has changed me. My focus shifted from just providing care for kids, to wanting to take care of the whole family. I discovered a love for truly comprehensive medicine, treating mind and body. I've overcome a lot of preconceived notions/fears of the mentally ill, and find myself led to try to help them, too. I can't just stop at treating the individual, though. The individual patient exists in the context of the family. The family exists in the context of the neighborhood, the county, the state...I have discovered that I'm unable to limit myself in caring for just one or two dimensions that make up my patients' existences. Thus, I find that I've become a social activist.
My political views have certainly changed as part of this. I was raised far-right, and naturally, those were my default views. I didn't do much independent thinking in undergrad either, but I got out "on my own" during medical school, and what I saw changed a lot of how I thought. It started with capital punishment- I'm now against it. I've seen what a lot of ruthless for-profit corporations have done to honest, hard-working people (and also less honest, less hard-working people, too). I'm a lot more sympathetic to the homeless and impoverished. The list goes on, but I find myself a just a bit left of center now. That's a far jump from the staunch conservative I used to be (I voted for McCain/Palin but try to forgive me...I'm voting for Obama in November.)
You'd probably not be surprised to find out that my changing views have disgruntled a few people in my life. When I told my wife that I was against the death penalty a few years ago, her response was, "I didn't marry a Democrat!" My thoughts on for-profit insurance companies, etc, don't always jive with those around me, either. In fact, I've found that many of my experiences in medical school, I can only really share with those who have gone on the journey as well, either with me or before me. I've seen people die. I saw a man shot in the head by a jealous girlfriend. I saw a woman who very nearly died of a heart attack in bed with her husband, but she lived. Children with incurable diseases, young adults with cancer, grandmothers and grandfathers with dementia. My hands have been inside people, I've been covered in their blood, I've worked 36 hours straight, the list goes on and on...
These experiences are hard to just tell other people about, and have them understand. I tried telling someone once about a man who came into the trauma bay with a leg broken and bleeding in many places. My job was to hold his leg still and straight while we moved him from the paramedic board onto the hospital gurney. I was sweating and my arms just felt horribly weak, but I knew I had to stay strong so I didn't hurt this man's leg any more than it was already. I resolved to get more in shape and increase my upper body strength, for him. So I wouldn't have to worry about my physical limitations causing one of my patients pain. The non-medical person I told this story to just didn't understand.
Just last week, someone told me "Doctors just don't care about patients." I hear all the time, "Doctors are stupid"; "They just push drugs (or vaccines) on you"; "They're in the pocket of the drug companies." There's some basis for these statements, of course, but I cringe whenever I hear them. More and more, I feel a close kinship to my colleagues...brothers and sisters in medicine. We've been through a LOT together. We've cried together...tears of joy and tears of sadness. We've sacrificed a LOT to be doctors...time (at least 8 years of education after high school), money (I'm exiting with $300,000 of debt), and immeasurable energy, emotion, care, and missed opportunities because we were working hard. Medical school has changed me a lot, and I hope with all my heart that all my experiences will make me an excellent doctor. We've been through a lot, we've done it together, and, even if we don't always do it well, we've done it with the one main goal of providing excellent care for you.