School of Public Policy & Management, Tsinghua University, Beijing 100084, China.
Jiyang College, Zhejiang Agriculture and Forestry University, Zhuji 311800, China.
Int J Environ Res Public Health. 2023 Jan 31;20(3):2522. doi: 10.3390/ijerph20032522.
Cost sharing and cost shifting mechanisms are of vital importance in a prospective payment system. This paper employed the difference-in-differences method to estimate the impacts of a per diem system with inverted-U-shape rates on medical costs and the length of stay based on data from a health insurance institution. The supply side cost sharing mechanism worked so that the new payment system significantly reduced medical costs by 17.59 percent while the average length of stay varied little. After further analyzing the mechanism, we found that heterogeneous effects emerged mainly due to the special rates design. The reform decreased the cases that incurred relatively high medical costs and lengths of stay. However, cost shifting existed so that physicians could be motivated to provide unnecessary services to the patients who should have been discharged before the average length of stay. Therefore, payment rates in the per diem system require a sophisticated design to constrain its distortion to medical service provision even though medical expenditures were successfully contained.
成本分担和成本转移机制在预付制中至关重要。本文利用双重差分法，基于某医疗保险机构的数据，估计了按天付费制与倒 U 形费率对医疗费用和住院时间的影响。供方成本分担机制使得新的支付系统显著降低了 17.59%的医疗费用，而平均住院时间变化不大。进一步分析该机制后发现，由于特殊费率设计，出现了异质效应。改革减少了那些医疗费用和住院时间相对较高的病例。然而，存在成本转移，因此医生可能会受到激励，为那些本应在平均住院时间之前出院的患者提供不必要的服务。因此，尽管成功地控制了医疗支出，但按天付费制的支付费率需要进行精细设计，以约束其对医疗服务提供的扭曲。
