Predictors of Specialty Training Program Selection after Two-year Legally Mandated Initial Clinical Training in Japan: A 10-Year Retrospective Single-center Cohort Study.

Objective To identify background factors associated with whether residents remain at the same institution for specialty training after completing initial clinical training or choose to transfer to a different institution. Methods We conducted a retrospective cohort study to analyze the demographic characteristics, geographic background, and recruitment interview data. Data were collected from the institutional records and recruitment interview documents obtained during the application process. A Firth-corrected logistic regression analysis was performed to identify the predictors of training continuation. Materials We studied 261 physicians who entered the mandatory two-year initial clinical training at the Jichi Medical University, Saitama Medical Center, between fiscal years 2012 and 2021. Physicians who had graduated from Jichi Medical University (under return-service obligations) were excluded. Participants were categorized into the Continuing Training (remaining at our institution) and Other Institution (trained elsewhere) groups. Results Among 261 participants who entered initial clinical training, 123 (47.1%) remained at our institution for specialty training. The General Medicine Open Course, which allows 28 weeks of elective rotation exclusively within our institution, was the primary independent predictor of retention. Firth-corrected logistic regression identified preference for the general medicine open course as an primary independent predictor (adjusted OR: 16.25, 95% CI: 1.78-2177; p=0.009). Conclusion Preference for the general medicine open course was independently associated with continuing specialty training at the same institution. This finding suggests that training courses providing extensive intra-institutional exposure may enhance institutional retention. These findings may inform recruitment strategies and training program designs; however, validation through larger multi-institutional studies is required.