Variation in per-diem fee-for-service payments between Friday and Monday surgeries for hip fracture: a nationwide observational study using DPC data

This dataset contains anonymised, aggregated data derived from a nationwide retrospective observational study examining the association between the day of surgery and per-diem fee-for-service (FFS) reimbursement among patients undergoing surgery for proximal femoral fracture in Japan. The study used Diagnosis Procedure Combination (DPC) administrative data collected from 185 acute care hospitals between April 2014 and July 2025. The dataset includes summary-level information on patient counts, surgical procedures (open reduction and internal fixation and hemiarthroplasty), day of surgery (Monday vs Friday), length of stay, major clinical outcomes, and decomposed components of per-diem FFS reimbursement (e.g., surgery-related, anaesthesia-related, laboratory testing, and imaging services). No individual-level identifiers are included. The data were generated to support analyses reported in a manuscript submitted to BMJ Quality & Safety, focusing on unwarranted temporal variation in healthcare delivery processes and reimbursement under a hybrid payment system. The dataset is intended to enhance transparency, reproducibility, and secondary research on health system performance, payment design, and quality improvement. Use of this dataset should acknowledge its origin from Japanese administrative claims data collected primarily for reimbursement purposes. Users should interpret findings in light of the limitations inherent to administrative data, including the absence of detailed clinical severity measures.