What did you intend to say was different about doctors back then?
The fact that today we have data on its effects on people who aren't high-willpower doctors.
You're answering a different question. First you said 19th-century doctors were especially willpowered, then you said willpower is also a factor in today's doctors. Now you say the difference is not willpower but the population examined. You're not only not giving any evidence for you claims; you're running in circles.
India vs. Pakistan: the nuclear option is dangerously close, and nobody seems to want to prevent it
http://qz.com/541502/a-nuclear-war-between-india-and-pakistan-is-a-very-real-possibility/