Evidence supporting professionalism as a critical measure of competence in medical education is limited. In this case-control study, we investigated the association of disciplinary action against practicing physicians with prior unprofessional behavior in medical school. We also examined the specific types of behavior that are most predictive of disciplinary action against practicing physicians with unprofessional behavior in medical school. The study included 235 graduates of three medical schools who were disciplined by one of 40 state medical boards between 1990 and 2003 (case physicians). The 469 control physicians were matched with the case physicians according to medical school and graduation year. Predictor variables from medical school included the presence or absence of narratives describing unprofessional behavior, grades, standardized-test scores, and demographic characteristics. Narratives were assigned an overall rating for unprofessional behavior. Those that met the threshold for unprofessional behavior were further classified among eight types of behavior and assigned a severity rating (moderate to severe). Disciplinary action by a medical board was strongly associated with prior unprofessional behavior in medical school (odds ratio, 3.0; 95 percent confidence interval, 1.9 to 4.8), for a population attributable risk of disciplinary action of 26 percent. The types of unprofessional behavior most strongly linked with disciplinary action were severe irresponsibility (odds ratio, 8.5; 95 percent confidence interval, 1.8 to 40.1) and severely diminished capacity for self-improvement (odds ratio, 3.1; 95 percent confidence interval, 1.2 to 8.2). Disciplinary action by a medical board was also associated with low scores on the Medical College Admission Test and poor grades in the first two years of medical school (1 percent and 7 percent population attributable risk, respectively), but the association with these variables was less strong than that with unprofessional behavior. In this case-control study, disciplinary action among practicing physicians by medical boards was strongly associated with unprofessional behavior in medical school. Students with the strongest association were those who were described as irresponsible or as having diminished ability to improve their behavior. Professionalism should have a central role in medical academics and throughout one's medical career. Copyright 2005 Massachusetts Medical Society.
