Whether or not you should do a DO internship depends on both the field
you wish to enter and the state in which you intend to practice. For
example, Arkansas, Maryland, Michigan, Pennsylvania and West Virginia
are the only states that still require an AOA internship (as of 1995).
Secondly, there are two types of ACGME residencies: categorical and
advanced. With categorical residencies your first year out of med
school is your PGY-1 year, in other words, you don't actually do an
internship per se. Depending on the field and program, they may or may
not accept your AOA internship as the PGY-1 year. Advanced residencies
on the other hand only take those who have completed an internship
(osteo or allo). Your first year in these programs would be as a PGY-2.
But again, whether or not they accept the osteo internship as your PGY-1
year depends on the program. Therefore, the basic problem, with either
type of residency is that one may find themselves doing the PGY-1 year
twice! The solution to this problem is to make sure you know the
requirements of all the programs you're interested in. The primary
source of info regarding residencies is the "Green Book" ie., the NRMP
directory. Keep in mind that if you don't live in one of the afore-
mentioned states, you can avoid all the confusion by foregoing the
internship altogether and just doing a categorical residency (assuming
the field you choose offers categorical programs). Hope this info helps.