Abstract
BACKGROUND: Timely treatment of infectious diseases is essential to prevent transmission and protect public health. However, the substantial direct economic burden often impedes infectious disease patients from accessing timely treatment. Currently, China has implemented an innovative payment model called Diagnosis-Intervention Packet (DIP) in 71 pilot cities. This study aims to evaluate the impact of DIP on the direct economic burden of infectious disease inpatients. MATERIALS AND METHODS: The dataset comprises 724,489 inpatient reimbursement records from City A spanning from January 2019 to June 2023. We conducted an interrupted time series analysis (ITSA) on six outcomes for a total of 2384 inpatients, with the top six being high-incidence Category B infectious diseases in City A. Further robustness analyses focusing on inpatients covered by Rural Residents Basic Medical Insurance (URRBMI), as well as those hospitalized for HBV and TB, were conducted to support our findings. RESULTS: Following the implementation of DIP, we observed downward trends in average inpatient expenditure (β(3) = -237.96, P < 0.01), average drug expenditure (β(3) = -164.21, P < 0.01), average inpatient out-of-pocket expenditures (OOPs) (β(3) = -124.58, P < 0.05), and the proportion of OOPs (β(3) = -0.31, P < 0.01). These correspond to monthly decreasing slopes of ¥237.96, ¥164.21, ¥124.58, and 0.31%, respectively. When analyzing the proportion of OOPs by catalog status, a significant decline was observed only for non-catalog items, with a decreasing slope of 0.19% (β(3) = -0.19, P < 0.01). The reintroduction of ITSA focusing on URRBMI inpatients, as well as HBV and TB inpatients, demonstrated the robustness of the results. CONCLUSION: The DIP appears to contribute to reducing the direct economic burden for patients with infectious diseases. On the one hand, DIP seems to facilitate a reduction in inpatient medical expenditures, particularly by containing drug expenditures, which constitute a major component of spending for infectious disease patients. On the other hand, the decline in the proportion of OOPs is primarily concentrated in out-of-catalog items, suggesting that the DIP model may help limit doctors' tendencies to shift costs onto patients.