Physicians are generally more religious than the general population:
http://www.uchospitals.edu/news/2005...religious.html
The ones that I know who aren't religious generally tend to be specialists in fields where they don't develop much of a patient-physician relationship(i.e anesthesiology, radiology). If you aren't religious you generally have a very hard time meeting the spiritual needs of your patients. More and more the medical field is recognizing how important a patient's spiritual health is to their overall well being.