Association between residents’ work hours and patient care ownership: a nationwide cross-sectional study in Japan

Purpose: In the current era of physician work-hour regulations, patient care ownership (PCO) has received considerable attention. The aim of the study was to investigate the association between working hours and PCO. Methods: This was a nationwide cross-sectional study. The study recruited residents who completed the General Medicine In-Training Examination. The primary outcome was PCO, assessed using the Japanese version of the PCO Scale (J-PCOS). The secondary outcomes were the four dimensions of the J-PCOS (i.e., assertiveness, sense of ownership, diligence, and being the “go-to” person). The explanatory variable was weekly working hours. We examined the association using multivariable linear regression analysis. Results: 1836 participants were included in the analysis. After adjustment for possible confounders, residents working ≥ 70 to < 90 h/week had greater PCO than those working ≥ 60 to < 70 h/week. Working ≥ 70 to < 90 h/week was also associated with assertiveness and being the “go-to” person. No clear trend was seen in the relationship between working hours and sense of ownership or diligence. Conclusion: While determining appropriate resident work hours requires comprehensive consideration of a number of factors, in terms of PCO training, the working hours of 80–90 h/week may be an option.