Shared Decision Making as a Policy and Clinical Framework for the Responsible Introduction of Repetitive Transcranial Magnetic Stimulation Therapy in Japan

Objective Repetitive transcranial magnetic stimulation (rTMS) has expanded in Japan since its inclusion under public insurance in 2019. This review examines systemic barriers to equitable adoption, ethical and legal challenges, and proposes Shared Decision Making (SDM) as a clinical and policy framework to ensure patient-centered care.Methods A narrative policy and practice review was conducted, synthesizing evidence from peer-reviewed studies, registry data, government guidance, and professional society statements. Comparative analysis with the United States and Europe was used to contextualize Japan’s distinctive financing and governance arrangements.Results Implementation of rTMS in Japan remains concentrated in tertiary hospitals and metropolitan centers, with limited diffusion to rural areas. Strict eligibility criteria under public insurance restrict access, while private-pay clinics have proliferated with heterogeneous protocols and variable disclosure practices. These structural imbalances generate inequities in access, ethical tensions regarding transparency, and legal concerns about informed consent. Additional barriers include limited public awareness, variability in provider expertise, and constrained outpatient consultation time. International comparisons highlight broader indications and more flexible reimbursement abroad, supported by stronger governance structures.Conclusion Embedding SDM into both insured and private rTMS practice in Japan is essential to safeguard equity, transparency, and sustainability. A pragmatic SDM framework, incorporating standardized information materials, AI-enabled decision aids, multidisciplinary collaboration, and registry-linked accountability, can transform rTMS adoption into a model of patient-centered governance. Institutionalizing SDM will not only improve treatment concordance and patient trust in Japan but also provide lessons for global mental health policy