Medical errors involving trainees: a study of closed malpractice claims from 5 insurers.

BACKGROUND Despite wide recognition that the delivery of medical care by trainees involves special risks, information about the types and causes of medical errors involving trainees is limited. To describe the characteristics of and factors contributing to trainee errors, we analyzed malpractice claims in which trainees were judged to have played an important role in harmful errors. METHODS The claims were closed between 1984 and 2004, and the errors occurred between 1979 and 2001. Specialist physicians reviewed random samples of closed malpractice claim files at 5 liability insurers from 2002 to 2004 and determined whether injuries had occurred, and if so, whether they were due to error. We described the clinical circumstances and contributing factors associated with harmful errors involving trainees ("cases"). We also compared the characteristics of cases with their nontrainee counterparts and probed trainee errors attributed to teamwork problems and lack of technical competence or knowledge. RESULTS Among 240 cases, errors in judgment (173 of 240 [72%]), teamwork breakdowns (167 of 240 [70%]), and lack of technical competence (139 of 240 [58%]) were the most prevalent contributing factors. Lack of supervision and handoff problems were most prevalent types of teamwork problems, and both were disproportionately more common among errors that involved trainees than those that did not (respectively, 54% vs 7% [P < .001] and 20% vs 12% [P = .009]). The most common task during which failures of technical competence occurred were diagnostic decision making and monitoring of the patient or situation. Trainee errors appeared more complex than nontrainee errors (mean of 3.8 contributing factors vs 2.5 [P < .001]). CONCLUSIONS In addition to problems with handoffs, house staff are particularly vulnerable to medical errors owing to teamwork failures, especially lack of supervision. Graduate medical education reform should focus on strengthening these aspects of training.