Doctors tend to have to do quite a lot of re-certification and continuing education. From https://en.wikipedia.org/wiki/Continuing_medical_education https://en.

Doctors tend to have to do quite a lot of re-certification and continuing education. From https://en.wikipedia.org/wiki/Continuing_medical_education https://en.wikipedia.org/wiki/Continuing_medical_education : n the United States, many states require CME for medical professionals to maintain their licenses. For example, Arizona requires an average of 40 hours of CME every two years.[4] For a complete list of requirements by state, see State Medical Licensure Requirements and Statistics, 2006. Within the United States, CME for physicians is regulated by the Accreditation Council for Continuing Medical Education (ACCME) and the American Osteopathic Association (AOA).