An independent study performed by The Associated Industries of Florida Service Corporation (AIFSC) has compared multi-specialty board requirements for both certification and re-certification. The study shows that the requirements of the three national certification organizations are generally equivalent.
The groups included in the comparison are: the American Board of Medical Specialties (ABMS), the American Board of Physician Specialties (ABPS), and the American Osteopathic Association's Bureau of Osteopathic Specialists (AOABOS).
The comparison brochure can be found here:
Source: American Association of Physician Specialists, Inc.