Assessment of the Impact of CHS-DRG Payment Reform on Hospitalization Costs in a Cancer Hospital Based on the Difference-in-Differences Method

Gao Ming; Liu Yi; Leng Jiahua

Abstract：Objective It aims to evaluate the overall impact of the CHS-DRG payment reform on hospitalization costs at a designated cancer hospital in Beijing.The research focuses on the differential effects of the reform on the costs of surgical,medical,and procedural care groups,and analyzes the trend of the reform's impact over time.Methods Utilizing inpatient case data from a specialized cancer hospital in Beijing,it employs the Difference-in-Differences method to assess the net effect on average hospitalization costs,with the DRG payment population as the intervention group and the non-DRG payment population as the control group.Event Study Plots are used to illustrate the estimated treatment effects at various time points before and after the intervention,revealing how the intervention effects change over time.Results The CHS-DRG reform led to a significant change in the average hospitalization costs for the intervention group(-518.82 RMB),particularly in the surgical(-3 071.72 RMB)and medical(-370.10 RMB)care groups.However,the impact on procedural care group costs was not significant.The effect of the reform showed a diminishing trend over time.Conclusion The reform effectively reduced hospitalization costs in the specialized cancer hospital,especially within the surgical and medical care groups,during its initial phase.The diminishing trend of the reform's effect indicates the need for further investigation into the long-term impacts of the system reform and optimization of internal management to consolidate the policy outcomes.