I was offered a 120k job through a friend at an oil company (my undergrad degree was in mechanical engineering). This was a month ago before I started MS1. That being said this was through a friend and I would have had to work long hours in foreign countries (at least initially). Engineering can make a lot of money and have great upward mobility in a corporation. In fact, there are more S&P 500 companies with CEOs with undergrad engineering degrees than business administrator degrees. (~21% v. ~15%) (Source:
http://content.spencerstuart.com/sswebsite/pdf/lib/Statistical_Snapshot_of_Leading_CEOs_relB3.pdf)
So I think it's a toss-up for some medical students depending on there previous professions and degrees. Some couldn't make more money in any other field, some could. I'm not willing to put a percentage on it.
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Concerning the silver spoon thing. Put yourself in a upper-class parental position. Say you make 140k a year and your son or daughter wants to go to med school. 30k a year our of 140k is a significant amount of money. Your lifestyle might change. You might have to skip a year between buying new cars or move into a smaller house because you can't afford the mortgage anymore. It would just be easier to tell the kid "your 22, you'll be a doctor, take out loans. I might help out a little bit."
That situation might change for the ultra rich. I don't know if there is data about it (if there is, let me know, I'm interested). Definitions of upper, middle, and lower-class change depending on who is using the statistics. If I wanted to make it look like med schools were full of a bunch of spoiled rich kids I would say 80K+ per household is upperclass.
Also, most people don't just "decide" to go to med schools, they have to work for it. Some can afford Kaplan courses, private tutors, etc. but in the end it was their MCAT score, their GPA, and their interview that got them in. I'm sure there is parental influence on schools, too... but thats not upper-class thats upper-upper-class (rich alumni, people of influence).
Ughh.. I'm too tired to proofread that.