I did about 40 of these, last one about 7 years ago. I got certified in by AADEP and ABIME.
Advantages:
--Paid really, REALLY well. Back then in my state, basically fee-for service.
Disadvantages:
--Working on deadlines, which I hadn't done since college. Unlike a clinic note, you have to show your work, citing tables and formulae. Once I started losing Saturdays, I was done.
--boring. It is not healthcare. It is accounting.
--Most patients seemed to be gaming the system. the rest getting royally screwed. The latter got to me more.
--Most of the work is not done in the clinic setting, but before and after. Since I don't work in private, this meant that I could bill for a clinic visit, then bill separately for the report. Had to pay someone to do my collections, then keep track of the 1099's.
--the more I did, the more complicated the requests became. That meant more boring for the same amount of work.
Was a good way to get out of debt, but I don't miss it.
Before investing any time and money, make very sure you know what guidelines your state requires. Mine uses AMA guides 6th ed, Florida used 4th, NC has their own... you get the idea. Whichever one you use, take a course.
Check on liability as well. Cases cited at courses mention patient alleged that the IME doctor hurt the him/her during exam, causing new injury, not covered during course of an IME. And just because you are not being sued, it doesn't mean that lawyers won't continue to bother you for clarifications.