Or possibly the term expresses a mistrust of the entire medical profession.
Marianna
I think there are bad doctors and good ones on both sides of the pond. I like my quack, he tells the truth whether you want it or not. I asked him if he thought a minor heart problem I was having was serious, he said if it was serious you'd be dead by now! and the last time I was talking to the nurse she said he had a woman in tears because she ( The nurses words) was a fat women who was having breathing and mobility problems and he told her it was because she was fat! You may think he sounds brash but I like that, no faffing about just comes right out and says it. When you leave his surgery you know exactly where you stand.