I'd grab a copy of Iserson's "Getting into a Residency," as it's full of great information and does talk about DO stuff in particular.
Let me quote a bit here (p. 351-353 of the Fifth edition); "..." means that I have cut stuff out, and a line break indicates paragraph breaks:
"As an Osteopathic physician, you have one of two different problems in getting a residency position, depending upon how you intend to approach your training: a limited number of Osteopathic residency positions, and the intransigence and constantly shifting rules of some Osteopathic licensing bodies.
"If you want to do specialty training in an Osteopathic residency, your main problem will be that there are relatively few slots form which to choose. The increase in Osteopathic medical students now far outpaces the increase in students at M.D. medical schools. Between 1970 and 2000, the number of D.O.s doubled, the number of Osteopathic medical schools incresaed from nine to nineteen, and the number of graduates nearly tripled. There are now more than 2,000 D.O. graduates annually. The number of Osteopathic residency slots, however, barely increaed. Those programs that do exist cannot accommodate the increasing percentage of young Osteopaths who want to pursue specialties other than primary care.
While the nearly 1,950 funded Osteopathic internships would be barely sufficient to meet the needs of Osteopathic graduates (if they all entered D.O. internships), the approximately 1,035 funded entry-level residency positions are far too few to accommodate the current number of Osteopathic graduates. This means that many Osteopathic graduates must look to the M.D. side of the profession for their training. The AOA's Osteopathic Matching Program and the military's matching program are the only ways to get an AOA-approved internship.
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The AOA, in its infinite wisdom, has made it very hard for you to pursue training at ACGME-approved programs.
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One way of circumventing the AOA is to train in an ACGME-approved program that has also been approved by the AOA. For internships, the AOA will approve (or has already approved) most Transitional (or equivalent) programs in the military. Technically, they ware also willing to give approval for other PGY-1 year ACGME-approved training. Don't count on this, however, since their track record is dismal.
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More Osteopathic graduates are entering ACGME-approved training programs each year....However, you must recognize that, for whatever reason, ACGME-approved training in some specialties is almost completely off-limits to Osteopaths. Chief among these are Diagnostic Radiology, General Surgery, and various sugical specialties, such as Colon and Rectal Surgery, Neurosurgery, Otolaryngology, Thoracic Surgery, and Urology. Even in the military, it is nearly impossible for an Osteopathic medical school graduate to obtain a position in, and be allowed to finish, a Surgical residency program. This is controlled by the "powers" granting accreditation to residency program. It may change in the future, but don't hold your breath.
If you apply to ACGME-approved program, make certain that you explain, in detail, exactly what your COMLEX scores mean (unless you took the USMLE-a smart move), what yor curriculum consists of, and what the grading scale on your transcript signifies. Remember that these may be significantly different from the scores, curricula, and granding scales seen in applications from M.D. students.
Also, be careful about your Dean's letter. While most Deans of Osteopathic medical schools send out respectable lettes which are comparable to those sent out by M.D. Deans, some send out almost cursory statements. One wonders if these are sent only to ACGME-approved programs, in an attempt to "keep you in the fold."
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Common Questions
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How much discrimination against D.O.s is there among M.D. residency directors?
To deny that many M.D. residency programs discriminate against D.O.s would be foolish. Many residency directors do not understand that Osteopathic training parallels that in M.D. schools. This discrimination, however, varies greatly by the area of the country and the specialty. Where many D.O.s practice and Osteopathic medical schools have been established, there is minimal discrimination - and what there is has been rapidly diminishing. Where there are few D.O.s, ignorance abounds. As to specialties, General Surgery and its subspecialties remain the major area that continues to reject virtually all D.O. residency applicants.