I think this is just part of the path to becoming a DO
I used to be all defensive (or aggressive) about educating people about DO - the philosophies, differences between US and foreign DOs, the stereotypes, etc.
But then I realized it just got more people confused.
Anyway, this is how I personally would have handled the situation
Bus driver: Oh - osteopaths are not real doctors. They don't learn as much, are dangerous, and can't find job.
Me: Are you sure you're talking about osteopathic physicians?
Bus driver: Yes (well, (s)he could say no but then it would be a moot point afterwards)
Me: Well, that's simply not true at all. In fact, osteopathic physicians learn more materials than MDs while in medical school. DOs have to take the same medical board licensing exams (or the equivalent) that MD students have, and must do the same residencies to be board certified. In fact, you have DOs working alongside MDs in almost every hospitals.
At this point, the bus driver will be "oh really, I didn't know that", or reaffirm that what you just said was not correct. If the bus driver maintains his/her position, just go "I dunno - are you sure we're talking about the same profession?"
The bus driver was not "knocking" you. He/She was just repeating what he/she has heard. This is a great opportunity to educate him/her. And in doing so, if this bus driver is gregarious and garrulous, will educate other people about osteopathic medicine.
You will be confronted with this situation a lot. You will be asked "What's a DO?" a lot. Be prepare to give a short (1-2 minute) reply.
Here's my advice (based on my short experience) on how to avoid confusing the person (otherwise, they'll start to think DO = chiropractor)
1. Start off by saying that DOs are doctors, just like MDs - and can do everything that MDs can do.
2. Mention that DOs like to view the whole patient when treating. Avoid words like "holistics" since those words will be registered in the person's mind as "alternative health care" or "homeopathy". Just mention "whole patient" and maybe give one or two examples.
3. Mention manual medicine but don't emphasize OMT (or OMM) too much. Emphasizing this will result in the person thinking DO = chiropractor. Mention that DOs also learn manual medicine to help patients cope with pain. There is no need to go into details about the philosophy behind OMM (and talk about somatic dysfunction or osteopathic lesions) unless they are interested in APPLYING to DO schools.
4. End by saying that DOs are licensed by the state medical board (no need to go into extreme details and talk about states w/ medical board and osteopathic medical boards - mention this only if they are interested in going into medicine). Mention that DOs have to take the same medical licensing exams (not exactly true but again, no need for finite details), and have to do residencies and fellowships to be board certified.
Don't make your reply sound like an essay. It should be around 1-3 minutes long. Emphasize the similarities but mention the differences. Hopefully the person will understand what DOs are (and not confuse it with homeopathy or chiropractics).
Wow - long reply (guess I didn't follow my 1-3 minutes rule)
OK, anatomy exam (head/neck) coming up - chao