When new rules capped training hours for US medical residents at 80 hours per week in 2003, critics worried that the change would leave physicians-in-training unprepared for the challenges of independent practice. Now, research led by scientists in the department of health care policy in the Blavatnik Institute at Harvard Medical School, shows that these dire warnings were largely unjustified.
The analysis – believed to be the first national study examining the impact of reduced hours on physician performance – found no evidence that reduced training hours had any impact on the quality of care delivered by new physicians.
Following a series of high-profile patient injuries and deaths believed to stem from clinical errors caused by fatigue, medical accreditation agencies initiated a series of sweeping changes to the regulations governing resident hours and other aspects of training. These efforts culminated in 2003 with the US Accreditation Council for Graduate Medical Education capping the training of medical residents at 80 hours per week.
“This is probably the most hotly debated topic in medical education among physicians,” said Anupam Jena, the HMS Ruth L Newhouse associate professor of health care policy in the Blavatnik Institute, a physician in the department of medicine at Massachusetts General Hospital and lead author of the study. “Many doctors trained under the old system think that today’s residents don’t get enough training under the new system. You hear a lot of senior physicians looking at younger doctors coming out of training and saying, ‘They’re not as prepared as we were.'”
The findings of the study should assuage these fears, Jena said.
The researchers found no significant differences in 30-day mortality, 30-day re-admissions, or inpatient spending between physicians who completed their residency before and after the residency hour reforms. “We found no evidence that the care provided by physicians who trained under the 80-hour-a-week model is sub-optimal,” Jena said.
Given the changes in hospital care over the past decade, the researchers knew that they couldn’t just compare the difference between outcomes of recently trained doctors before and after the cap, since overall outcomes have improved thanks to better diagnoses and treatments, better coordination of care and new digital tools designed to prevent harmful drug interactions and other human errors.
Comparing new physicians trained before reform with those trained after would confound the effect of changes in training with the effect of overall changes in hospital care. To avoid conflating the two, the researchers compared new physicians before and after the reforms with senior physicians who had trained before the reform.
The study analysed 485,685 hospitalisations of Medicare patients before and after the reform. The training hour reforms were not associated with statistically significant differences in patient outcomes after the physicians left training.
For example, 30-day mortality rates among patients cared for by first-year attending internists during 2000-2006 and 2007-2012 were 10.6% (12,567/118,014) and 9.6% (13,521/140,529), respectively. In comparison, the 30-day mortality among patients cared for by tenth-year attending physicians was 11.2% (11,018/98,811) and 10.6% (13,602/128,331) for the same years.
Further statistical analysis to eliminate the unwanted effects of other variables showed that these differences translated into a less than 0.1 percentage point gap between the groups. The difference in hospital readmission rates was similarly minuscule: 20.4% for patients cared for by first-year physicians in both 2000-2006 and 2007-2012, compared with 20.1% and 20.5%, respectively, among patients treated by senior physicians.
Taken together, these findings suggest that US residency work hour reforms have not made a difference in the quality of physician training, Jena said.
As a way of magnifying any possible gaps in care stemming from a difference in training hours, the researchers looked specifically at outcomes for high-risk patients, in whom even small differences in quality of care would become apparent.
“We looked at patients who were particularly ill. In these cases, one little mistake could mean the difference between life and death,” Jena said. “Even for these sickest patients we found that the reduced training hours had no effect on patient mortality.”
Objective: To determine whether 30 day mortality, 30 day readmissions, and inpatient spending vary according to whether physicians were exposed to work hour reforms during their residency.
Design: Retrospective observational study.
Setting: US Medicare.
Participants: 20% random sample (n=485 685) of Medicare beneficiaries aged 65 years or more admitted to hospital and treated by a general internist during 2000-12.
Main outcome measures: 30 day mortality, 30 day readmissions, and inpatient Medicare Part B spending among patients treated by first year internists who were fully exposed to the 2003 Accreditation Council for Graduate Medical Education (ACGME) work hour reforms during their residency (completed residency after 2006) compared with first year internists with partial or no exposure to reforms (completed residency before 2006). Senior internists not exposed to reforms during their residency served as a control group (10th year internists) for general trends in hospital care: a difference-in-difference analysis.
Results: Exposure of physicians to work hour reforms during their residency was not associated with statistically significant differences in 30 day mortality, 30 day readmissions, or inpatient spending. Among 485 685 hospital admissions, 30 day mortality rates during 2000-06 and 2007-12 for patients of first year internists were 10.6% (12 567 deaths/118 014 hospital admissions) and 9.6% (13 521/140 529), respectively, and for 10th year internists were 11.2% (11 018/98 811) and 10.6% (13 602/128 331), for an adjusted difference-in-difference effect of −0.1 percentage points (95% confidence interval −0.8% to 0.6%, P=0.68). 30 day readmission rates for first year internists during 2000-06 and 2007-12 were 20.4% (24 074/118 014) and 20.4% (28 689/140 529), respectively, and for 10th year internists were 20.1% (19 840/98 811) and 20.5% (26 277/128 331), for an adjusted difference-in-difference effect of 0.1 percentage points (−0.9% to 1.1%, P=0.87). Medicare Part B inpatient spending for first year internists during 2000-06 and 2007-12 was $1161 (£911; €1024) and $1267 per hospital admission, respectively, and for 10th year internists was $1331 and $1599, for an adjusted difference-in-difference effect of −$46 (95% confidence interval −$94 to $2, P=0.06).
Conclusions: Exposure of internists to work hour reforms during their residency was not associated with post-training differences in patient mortality, readmissions, or costs of care.
Anupam B Jena, Monica Farid, Daniel Blumenthal, Jay Bhattacharya