Research on Effects of DIP Payment Reform on Physician Practices by Department:A Hospital-Based In-terrupted Time-Series Study

Cao Xiaolin; Sui Mengyun; Su Xiaopei; Chang Zhaoyu; Zhang Fengluan; Zhou Xin; Zong Jiazhen

Abstract：Objective To explore the changes in physicians'diagnostic and treatment behaviors before and after the implementation of the Diagnosis-Related Group(DIP)reform,providing evidence for healthcare payment reform.Methods It selected a tertiary hospital in W City,Shandong Province,as a sample and analyzed indicators of physicians'diagnostic and treatment behaviors using an interrupted time series analysis.Results The differences were statistically significant on the trend changes in the increased number of hospitalizations and decreased average hospitalization expenses in surgical departments.The overall average length of stay decreased but not significantly.Although the hospital CMI increased,its trend change decreased significantly.The CMI of internal medicine departments increased,while that of surgical departments decreased.Conclusion The DIP payment reform has a structural impact on the service volume of internal medicine and surgery,driving resources towards surgery.The potential risk of patient deferral needs to be vigilant.DIP reform effectively controls cost growth but is accompanied by a decrease in the difficulty of admitted cases,highlighting the need to balance controlling medical cost growth with incentives for admitting severe cases.Changes in the average length of stay reflect differences in efficiency responses across departments,with improved efficiency evident in surgical departments,while optimization of internal medicine processes still needs to be strengthened.