Limiting first-year medical residents to 16-hour work shifts, compared to “flexing” them to allow for some longer shifts, generally makes residents more satisfied with their training and work-life balance. It also makes their training directors more dissatisfied with curtailed educational opportunities, a new study from the New England Journal of Medicine has found.

For the study, investigators from the Johns Hopkins School of Medicine and the Perelman School of Medicine at the University of Pennsylvania surveyed and tracked the activities of thousands of first-year residents in 63 internal medicine training programs nationwide. The study—which is part of a five-year effort funded by the National Heart, Lung, and Blood Institute and the Accreditation Council for Graduate Medical Education (ACGME)—also found that shift-length regulations have no effect on the residents’ activity or test of medical knowledge scores one way or the other.

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