But the residents didn't actually get any more sleep under the limited work hours policy. And they also said they felt less prepared as doctors and were less satisfied with their education.

In July 2003, the Accreditation Council for Graduate Medical Education implemented new policies limiting the on-duty hours of notoriously sleep-deprived residents to 80 per week, with a minimum of 10 hours off between shifts. Those changes were further updated in 2011.

The main goal of the shift was to ease young doctors' fatigue and fatigue-related medical errors.

Although the work limits seem to have been somewhat successful, they do come at a cost, according to Dr. Debra Weinstein from Massachusetts General Hospital and Brigham and Women's Hospital in Boston, who worked on the new study.

"The extent to which we restrict residents' time in the hospital does risk (affecting) their skill and their sense of preparedness," she told Reuters Health.

There are still questions about the impact of the work restrictions, as well as groups who continue to push for tougher requirements, Weinstein said. But, she added, "Continuing to further limit duty hours may not be the best way to address the goals of patient safety, resident well-being and excellent medical education."

Some past studies have suggested work limits improve quality of life for residents, but negatively impact their education. One survey published last year found the majority of surgery residents worked more hours than the current regulations allowed (see Reuters Health story of February 24, 2011).

For the new study, researchers analyzed surveys completed by a total of 216 residents at the Harvard Orthopedic Combined Residency Program between 2003 and 2009.

Compared to pre-policy 2003 residents, orthopedic trainees in 2009 reported working fewer hours per week - about 66 hours, versus 75. But they didn't get any more sleep. Throughout the study period, residents reported sleeping for about five hours every night, on average.

After the work-hour policies went into place, residents did say they spent fewer days feeling very tired, and a smaller proportion of them said their fatigue had a negative impact on patient care and safety.

Forty-six percent of residents said their fatigue affected the quality of care they provided in 2003, compared to 26 percent on the 2004 through 2009 surveys.

"There's a general assumption that reducing work hours will result in more sleep for tired residents, and clearly our findings challenge that," Weinstein said. However, it's possible having more time to decompress and relieve psychological stress may improve residents' sense of well-being, even if they're not getting more sleep, according to her team.

Residents rated their own preparedness to make clinical decisions under stress and their ability to perform the range of skills expected of them slightly lower in later years, the researchers reported in the Annals of Surgery.

Weinstein and her colleagues noted that their study didn't include objective measures of residents' performance - so they couldn't tell whether residents did better or worse on exams or made more or fewer errors under their more-limited work schedule.

But, she said policymakers should consider both the benefits and drawbacks of further limiting residents' hours, both for the residents themselves and for the patients they treat.

"We have to be cautious in developing new policy and probably make small incremental changes that are based on good research," Weinstein said.

SOURCE: bit.ly/TcFx66 Annals of Surgery, online October 12, 2012.

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