Focus on MP: Evolution of Medical Physicist Certification by the ABR
By ABR Board of Trustees Chair Matthew B. Podgorsak, PhD; ABR Trustees Jennifer Stickel, PhD, and Sameer Tipnis, PhD; and ABR Associate Executive Director for Medical Physics Geoffrey S. Ibbott, PhD
April 2026;19(2):6
The March 2020 issue of The Beam included an article written by Don Frey, PhD, associate executive director for medical physics at the time, in which he outlined the history of the development of certification boards, including the ABR, and how medical physicists came to be certified by the ABR.
The following is a summary of the portion of Dr. Frey’s article that focused on the history of the ABR’s medical physicist certification program.
There are 24 Member Boards of the American Board of Medical Specialties (ABMS). The ABR is one of only two that certify nonphysician professionals. The other is the American Board of Medical Genetics and Genomics.
The ABMS was formed in 1933, with the following inaugural Member Boards: the American Board of Ophthalmology, the American Board of Obstetrics and Gynecology, and the American Board of Otolaryngology – Head and Neck Surgery. The motivation for developing the ABMS was to support professional development of physicians by setting consistent standards indicating competence that could be applied irrespective of a physician’s specialty practice. The ABMS also became a repository of board certification status to which the public could refer when selecting a provider.
During the American College of Radiology’s (ACR) 1932 annual meeting, then–ACR president Arthur Christie, MD, stated the desirability of creating an organization that could evaluate the competence of physicians who were employing x-ray-based technologies in their practices. Over the next two years, the ACR collaborated with the other three major national radiology societies at the time — the American Roentgen Ray Society (ARRS), the Radiological Society of North America (RSNA), and the American Radium Society (ARS) — to lay the groundwork for an organization charged with setting standards and creating certifying exams for radiologists. The aim was to protect patients by ensuring radiologists had met rigorous education and training standards. This led to the founding of the ABR in January 1934. Henry Pancoast, MD, was the first physician certified by the ABR and subsequently served as its first president.
The need to certify medical physicists was identified in the early 1920s, a time when there was no formal education for medical physicists and most were trained on the job in radiation therapy facilities where they performed calibrations of radiation therapy equipment for both teletherapy and brachytherapy applications. The American Association of Physicists in Medicine (AAPM) did not exist, so the RSNA undertook the initiative to certify medical physicists.
By the late 1930s, there was a movement among radiologists and medical physicists to have the ABR take over certification of medical physicists given the close working relationship they had with radiologists and therapeutic radiologists (known today as radiation oncologists), for whom ABR certification programs already existed. Negotiations to implement this transition were delayed by World War II; however, in 1947, the RSNA officially transferred certification authority of medical physicists to the ABR.
The first group of medical physicists was certified by the ABR on November 24, 1947, and included Paul Abersold, Karl Morgan, Marvin Williams, and Edith Quimby, among others. The first formal certification exams for medical physicists were administered in 1949. To date, there are well over 10,000 medical physicists who have been certified by the ABR or are currently in the certification process.
Beginning in 1947 and continuing through 1970, most medical physicists received a “radiological physics” certificate. This certification was meant to indicate competence in a broad scope of practice in diagnostic imaging physics and radiation therapy physics. Not long after the broader application of radioactive material for therapeutic and diagnostic intent in the late 1940s and early 1950s, the need for a more focused evaluation of a medical physicist’s competence within this practice was identified. Starting in 1954, board certifications for medical physicists practicing with this material started indicating nuclear medical physics specialization, with most still holding the radiological physics certificate.
In the mid-1970s, there was tremendous refinement in diagnostic imaging and radiation therapy technologies, and the need for medical physicist certifications specific to these individual practice profiles became clear. Issuing of the radiological physics certificate was thus discontinued, and certifications in diagnostic medical physics, therapeutic medical physics and nuclear medical physics were subsequently offered. These three certificates continue to be offered to medical physicists today.
Over the past century, medical physicists have shared a longstanding working collaboration with our radiologist and radiation oncologist colleagues. Our professions have benefited from synergies that have occurred through combined ingenuity and talent, and this will continue. Being certified by a board that also certifies the clinical colleagues with whom we share responsibility for patient care is intuitive and provides additional safeguards for patients. The ABR will continue to support safe and effective patient care within the radiologic fields by fulfilling its mission: certifying that its diplomates demonstrate the requisite knowledge, skill, and understanding of their disciplines to the benefit of patients.
