Many doctors can tell stories of being interns and working 30-hour shifts that kept them awake for nearly 36 hours at a time. And, many doctors believe that all new doctors should be able to recount these same stories years down the road. However, there was enough opposition to the long hours that new rules will restrict new interns to 16-hour shifts.

The independent nonprofit group that regulates residency programs, the Accreditation Council for Graduate Medical Education, restricted the number of hours first-year interns can work after research exploring the hazards of fatigue led to concerns over patient safety. This is the second major restriction on hours by the council in the past decades.

In 2003, the council restricted interns to working 80 hours per week, mandated at least one day off per week, and prohibited direct patient care after 24 hours of continuous duty. However, two major studies published in the past two years indicate that limiting hours to 80 hours per week had no effect on the number of medical errors occurring.

A small study published in the New England Journal of Medicine in 2004 indicated limiting the number of hours interns could work per shift had a significant impact on the reducing medical errors. The study looked at a group of interns working traditional 30-hour shifts and a group of interns working 16-hour shifts. The New York Times reports that the results showed that the interns working the traditional long-shifts made 36 percent more major medical errors than the interns working shorter shifts.