Residency programs in the United States have changed and, in the face of health care reform, will certainly continue to do so. It seems imperative that we assess the effect of these changes on the educational value of postgraduate medical training and on the quality of patient care in teaching hospitals. In their article, Petersen and colleagues [1] focused on only one of the recent modifications: the decrease in weekly work time for each individual resident, which is offset by cross-coverage arrangements or night float systems. The data they present confirm their hypothesis that cross-covering residents caused more adverse events than did the primary care team. Considering the potential implications of this finding, the main conclusion is weak. The authors relied entirely on self-reported adverse events, without any attempt to validate this method. Such an approach is susceptible to reporting bias. This shortcoming weighs even more heavily because the statistical power of their study is (as the authors admit) low.

My objections, however, go beyond methodologic weaknesses. The article raises a series of questions that the authors failed to address. If these findings could be confirmed in other studies with more appropriate methods, do they only reflect reality in teaching institutions? Cross-coverage is clearly not a phenomenon unique to academic medical centers. Thus, must we demand from all U.S. physicians that they be constantly available? Additionally, if we require our residents to live in hospitals, do the residency programs continue to meet their goal to train responsible physicians? We should remember that education is not only a function of time spent in an institution.

Many years ago, I learned the Latin phrase "mens sana in corpore sano." This rule probably applies to physicians and resident physicians. An exhausted, sleep-deprived body may not be the ideal of sanity for which we should strive. We should clearly be responsible for our patients, but we should also not neglect ourselves.