NCPA - National Center for Policy Analysis


November 2, 2004

First-year medical residents who work too many hours make significantly more medical errors and have more lapses in attention because of fatigue than those who got more sleep, find two new studies published in the New England Journal of Medicine.

Researchers observed residents over a six-week period, three weeks of which were spent in an 80-hour work schedule and another three weeks working 60 hours. The two studies found that:

  • Residents working 80-hours a week (including a 24- to 34-hour shift every 3 days) committed 35 percent more serious medical errors than when they worked on a lighter schedule, with a maximum shift of 17 hours.
  • Residents working the longer schedule were more than twice as likely as those working the shorter shifts to display fatigue, such as eyes rolling back into the head and nodding off.

Medical errors included misdiagnosing patients, ordering the wrong medication or dose, incorrectly interpreting the results of tests or making a mistake during a procedure.

According to the researchers, the results show that in addition to limiting the total number of hours residents should work, more attention should be paid to the length of the shifts. They add that the studies challenge the notion that it's safe to deliver patient care after working 30 consecutive hours.

Source: Steven W. Lockley et al., "Effect of Reducing Interns' Weekly Work Hours on Sleep and Attentional Failures," New England Journal of Medicine, Vol. 351:1829-1837, No. 18, October 28, 2004; and Christopher P. Landrigan et al., "Effect of Reducing Interns' Work Hours on Serious Medical Errors in Intensive Care Units," New England Journal of Medicine, Vol. 351:1838-1848, No. 18, October 28, 2004.

For Lockley study (subscription required)

For Landrigan study (subscription required)


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