Changes over time in the knowledge base of practicing internists.

OBJECTIVE To determine factors affecting the knowledge base of practicing internists. DESIGN An 82-item multiple-choice examination with questions from the 1988 American Board of Internal Medicine (ABIM) certifying examination was used to assess the knowledge base of 289 internists. SETTING AND PARTICIPANTS Participants were selected from among practicing internists in New York, New Jersey, and Pennsylvania who had received ABIM certification 5 to 15 years previously. RESULTS significant inverse correlation (r = -.30) was found between examination scores and the number of years elapsed since certification. Knowledge declined sharply within 15 years of certification. In addition, procedure-oriented subspecialists (cardiologists and gastroenterologists) had lower scores than other internists in this examination of general medical knowledge. Multivariate analyses showed that independent variables that predicted test performance were initial ABIM certifying examination score, time elapsed since certification, subspecialty classification, medical school type, and residency type. CONCLUSIONS These results support the recent decision for time-limited certification of internists and raise questions related to content and standard setting for recertification examinations.