Impact of diagnosis-intervention packet payment reform on pediatric hospital services: an interrupted time series analysis

BACKGROUND: Diagnosis-Intervention Packet (DIP) reform has been widely implemented in China, but its impact in pediatric settings remains unclear. This study evaluated its effects on pediatric admissions, case severity, efficiency, and expenditures in a tertiary maternal and child hospital in Guangzhou. METHODS: Pediatric inpatient discharge data (0-18 years) from January 2016 to December 2019 were analyzed using an interrupted time series design. Outcomes included total admissions, proportion and number of complex/critical and non-local complex/critical cases, mean length of stay (LOS), and mean total expenditure per case. Subgroup analyses by major disease categories and sensitivity analyses were performed to assess the robustness and heterogeneity of reform effects. RESULTS: A total of 93,396 pediatric discharges were included, with 45,493 discharges in the pre-reform period and 47,903 in the post-reform period. The DIP reform was associated with significant long-term changes in pediatric service utilization and expenditure. Specifically, the monthly slope of total pediatric admissions decreased slightly after the reform (β = -0.006, P < 0.001). Similar decreasing trends were observed for the proportion of complex/critical cases per month (β = -0.018, P < 0.001), the absolute number of complex/critical cases (β = -0.017, P < 0.001), the proportion of non-local complex/critical cases (β = -0.012, P < 0.001), and the absolute number of non-local complex/critical cases (β = -0.016, P < 0.001). In terms of service efficiency, the post-reform monthly slope of mean LOS showed a reduction after accounting for lag periods, whereas mean total expenditures per case showed a statistically significant decrease (β = -0.010, P = 0.001). CONCLUSIONS: The DIP payment reform was associated with decreases in total pediatric admissions, as well as in the proportion and number of complex/critical and non-local complex/critical cases. Mean LOS showed a delayed decrease following the reform, while per-case total expenditures showed a decreasing trend over time.