I got to thinking about this after leaving my Dermatologist's office this afternoon. And I wonder if the medical speciality makes any difference.
As a provider, I can tell you first hand that there are many of us Atheists within the healthcare industry. At just my agency, we have several (more than 5 admitted agnostic/atheist). As far as providers outside of my agency, I know of a few. The others, I don't suspect of being that devout. The biggest irony tho, is while healthcare providers (in my experience, so admittedly anecdotal) tend to be secular, the other Emergency Services (PD & FD) tend to be more religious.
I have a classmate who is a surgeon that made snarky comments about indoctrination and the church so I asked him whether he is atheist or catholic. He went with agnostic.