I can't think of one. Most hospitals merely require board certification in your specialty. I don't believe there is any distinction whether ABA or AOBA. Its an added expense imo. Back in the day I considered taking ABA and AOBA boards. When I looked into doing it, since I was at an allopathic residency, I was informed I would first have to have an AOBA examiner come and spend time at my program to see if it met their board criteria. I would have to pay all expenses for the examiner. Amazingly, my PD, Machiavelli himself, agreed to go along. After about a millisecond of thinking it over, I told the AOBA basically to go sh1t in their hat. It is a distinction without a difference, imo. Although years later, I received numerous emails offering me the opportunity to sit the AOBA boards which I quickly deleted. Boards and recertification are very much about the money.