I am talking about US. Doctors are certified, but not all are bo

Board certified requires more tests. If you look at the list of doctors provided by your health insurance company, you will see some are board certified, but some are not. Other than MD, there are nurse practioners (Nurses who got some kind of certificate which allows them to see patient and perscribe medicine. I would not pick anyone who is not board certified because it means they have taken the short cut, or have not kept up to date.