Extended work shifts and the risk of motor vehicle crashes among interns.
BACKGROUND
Long work hours and work shifts of an extended duration (> or =24 hours) remain a hallmark of medical education in the United States. Yet their effect on health and safety has not been evaluated with the use of validated measures.


METHODS
We conducted a prospective nationwide, Web-based survey in which 2737 residents in their first postgraduate year (interns) completed 17,003 monthly reports that provided detailed information about work hours, work shifts of an extended duration, documented motor vehicle crashes, near-miss incidents, and incidents involving involuntary sleeping.


RESULTS
The odds ratios for reporting a motor vehicle crash and for reporting a near-miss incident after an extended work shift, as compared with a shift that was not of extended duration, were 2.3 (95 percent confidence interval, 1.6 to 3.3) and 5.9 (95 percent confidence interval, 5.4 to 6.3), respectively. In a prospective analysis, every extended work shift that was scheduled in a month increased the monthly risk of a motor vehicle crash by 9.1 percent (95 percent confidence interval, 3.4 to 14.7 percent) and increased the monthly risk of a crash during the commute from work by 16.2 percent (95 percent confidence interval, 7.8 to 24.7 percent). In months in which interns worked five or more extended shifts, the risk that they would fall asleep while driving or while stopped in traffic was significantly increased (odds ratios, 2.39 [95 percent confidence interval, 2.31 to 2.46] and 3.69 [95 percent confidence interval, 3.60 to 3.77], respectively).


CONCLUSIONS
Extended-duration work shifts, which are currently sanctioned by the Accreditation Council for Graduate Medical Education, pose safety hazards for interns. These results have implications for medical residency programs, which routinely schedule physicians to work more than 24 consecutive hours.
Barger
Laura K
LK
Division of Sleep Medicine, Department of Medicine, Brigham and Women's Hospital, Boston, MA 02115, USA.
Cade
Brian E
BE
Ayas
Najib T
NT
Cronin
John W
JW
Rosner
Bernard
B
Speizer
Frank E
FE
Czeisler
Charles A
CA
D000063:Accidents, Traffic / Q000706:statistics & numerical data*; D001334:Automobile Driving; D005221:Fatigue / Q000150:complications; D006801:Humans; D007396:Internship and Residency / Q000458:organization & administration; D016017:Odds Ratio; D010561:Personnel Staffing and Scheduling; D011446:Prospective Studies; D012306:Risk; D012890:Sleep; D012892:Sleep Deprivation / Q000150:complications; D011795:Surveys and Questionnaires; D014481:United States; D014940:Work Schedule Tolerance / Q000502:physiology; D016526:Workload