The American Osteopathic Board of Radiology (AOBR)  requires graduation from an osteopathic medicine college and offers initial certification and recertification. Applicants must pass a combined diagnostic imaging and physics examination in the third postgraduate year and then complete a 4.5-hour oral examination in the fourth year or later. For recertification, the AOBR has recently transitioned from an examination every 10 years to a continuous certification cognitive assessment format, requiring the completion of 15 self-assessment modules during each 3-year CME cycle.
The American Board of Physician Specialties (ABPS)  also has a board of certification in radiology, with initial board certification in diagnostic radiology requiring both written and oral examinations. An ABPS time-limited certificate is valid for eight years. Recertification then requires 20 continuing medical education credits per year plus at least 50 self-assessment CME questions per year.
The National Board of Physicians and Surgeons (NBPAS)  offers a maintenance of certification product that includes radiology. However, as of March 23, 2020, just 132 hospitals, approximately 1% of hospitals nationwide, recognized the NBPAS MOC certificate, and no insurance company accepted it. NBPAS entering the marketplace has heightened awareness of issues related to MOC.