Required psychiatry rotation in residency training enhances psychiatric competence: A nationwide study in Japan

To address the need to integrate mental health into primary care, Japan introduced a mandatory one-month psychiatry rotation within the two-year postgraduate clinical training program in 2020. However, it remains unclear whether the required rotation improves psychiatric competence, and concerns exist that it might reduce learning opportunities in other fields. This study evaluated the association between the duration of psychiatry rotation and residents' psychiatric and overall clinical competence, measured by a nationwide examination. We conducted a cross-sectional study among 5905 residents taking the General Medicine In-Training Examination (GM-ITE). Using linear mixed-effects models, we examined the association between psychiatry rotation duration (none, 1, 2, ≥3 months) and percentage scores on the psychiatry section (4 questions) and the total examination (80 questions). Models were adjusted for covariates including sex, postgraduate year, hospital settings, and career preference for psychiatry. Compared with residents without psychiatry rotation experience, those with 1, 2, and ≥ 3 months of rotation had significantly higher psychiatry scores, with adjusted mean differences of 5.6% (95% CI: 3.5-7.6), 8.7% (4.4-13.0), and 10.2% (2.8-17.7), respectively. In contrast, no significant difference was observed in total scores regardless of rotation durations. In summary, psychiatry rotations of one month or longer were significantly associated with improved psychiatry scores, without compromising overall clinical learning. These findings support the educational value of required psychiatry rotations and provide an evidence-based perspective for curriculum development and training time allocation in residency programs worldwide.