In the NCAA, the three divisions (I, II, and III) are separated based on the athletic scholarships that the schools can offer. I can't find any information about the similar divisions in the NAIA, other than that the NAIA Division I is comparable to NCAA Division II in skill. Is skill the only difference between NAIA DI and DII?
I found that in the past, it was based on enrollment, but that no longer seems to be the case. For example, Arizona Christian University has ~781 students and is DI. Aquinas College in Michigan is DII, yet has ~2000 students. Any insight is appreciated.