When I was a highway cop I had a lot of medical people stop to "help." I learned real quick, in the case of doctors especially, to ask their specialty. If they said something like proctologist I sent them on their way with my thanks. If they said paramedic or ER nurse I gave them my EMT kit and got out of their way. It was funny, paramedics, EMT, nurses, firefighters, etc, would run up and say "I'm a so and so, can I help?
Doctors, on the other hand, just say "I'm a doctor." As if that means they are actually well versed in non-sterile environment medical treatment...

Unless confronted with proof to the contrary, always assume all physicians who present themselves at accident scenes to be proctologists.

very good point! Amazing how many MD's know little about emergency or trauma procedures.