BackgroundIn Japan, the “Work Style Reform Bill” was partially enacted in 2019. In 2011, an Overnight Call Shift (OCS) system was introduced for pediatric training at the National Center for Child Health and Development (NCCHD). A questionnaire survey was conducted twice during the introduction of this system, finding a decrease in working hours, but no change in the depressive tendency of the residents. We conducted a follow-up survey in 2019 to investigate the long-term effectiveness of the OCS system to improve the pediatric residents’ wellness at NCCHD.MethodsA questionnaire-based cross-sectional survey was conducted for pediatric residents in 2019, and the results were compared to those of the previous survey in 2012. The questionnaire includes demographic data, working conditions data, and wellness assessment by the Center for Epidemiologic Studies Depression scale (CES-D) and the Maslach Burnout Inventory (MBI).ResultsThe collection rate for the 2019 survey was 94.5% (37 participants/39 eligible). Compared to 2012, there were no significant changes in demographic data and working hours, a significant increase by about 30% in residents who took daytime off after night work, about 10% decrease in residents who scored 16 and above on the CES-D, and a significant decrease in the mean score for depersonalization (DP) in the MBI.ConclusionsThis survey demonstrated the long-term effectiveness of the implemented OCS system to improve pediatric residents’ wellness. This study provides evidence for the further initiative to improve pediatricians’ wellness for preparing for the government’s overtime regulations for physicians scheduled for 2024.