Work Hours, Stress, and Burnout Among Resident Physicians.

Importance: Burnout is highly prevalent among resident physicians, producing serious personal, professional, and system consequences. While work hour restrictions were implemented to improve patient safety and resident fatigue, the relationship between work hours with burnout and well-being remains unclear. Objective: To evaluate the association of work hours with burnout, stress, and self-perceived competency among residents in high-burnout specialties, and to explore potential demographic and well-being-related moderators. Design, Setting, and Participants: This cross-sectional study included responses from a remote survey conducted from February to June 2024 as part of a randomized clinical trial evaluating a well-being intervention among resident physicians. Eligible participants were residents enrolled in high-burnout specialty residency programs (surgery, obstetrics-gynecology, family, internal, and emergency medicine) in the US. Exposure: Self-reported average weekly work hours and total hours worked in the past week. Main Outcome and Measures: Burnout, stress, and self-assessed Accreditation Council for Graduate Medical Education (ACGME) competency milestones, adjusting for demographics. Results: A total of 540 residents responded (356 cisgender women [66.8%]; 112 Asian [21.1%], 28 Black [5.3%], 355 White [67.0%]). The sample was predominantly in a medical specialty (56%). The mean (SD) number of average hours worked was 65.4 (11.3) and the mean (SD) number of hours worked in the last week was 60.1 (17.4). There was no significant association between burnout and average hours worked (β = 0.05 [95% CI, -0.05 to 0.15]; P = .34) or hours worked last week (β = 0.06 [95% CI, -0.03 to 0.15]; P = .21). However, stress was positively associated with average hours worked (β = 0.17 [95% CI, 0.07 to 0.26]; P = .001) and hours worked last week (β = 0.27 [95% CI, 0.18 to 0.36]; P < .001). Self-assessed ACGME competency milestones were also positively associated with average hours worked (β = 0.14 [95% CI, 0.07 to 0.21]; P < .001) and hours worked last week (β = 0.08 [95% CI, 0.01 to 0.15]; P = .02). Despite exploring a large set of candidate moderators, very few moderators were identified and none survived P value adjustment. Conclusion and Relevance: In this cross-sectional nationwide study of resident physicians in high-burnout specialties, longer work hours were associated with higher stress and self-perceived competency, but not with burnout. This suggests that work hours alone may not explain high burnout levels in residency; a more comprehensive approach beyond work hour restrictions is needed to support resident well-being in training.