Objective To analyze the impact of diagnosis-intervention packet (DIP) payment method on the medical service structure and outpatient-inpatient structure.

Methods Data were collected from public medical institutions in DIP pilot city A and non-DIP reform city B in China from 2019 to 2022. Descriptive and difference-in differences-analyses were conducted on the medical service structure (medical service costs, drug costs, material costs, and examination and testing costs) and outpatient-inpatient structure (outpatient and inpatient costs, outpatient visits, and number of inpatient discharges).

Results In terms of medical service structure, the examination and testing costs in city A decreased by 19.0% compared with those in city B (P < 0.05). In terms of the outpatient-inpatient structure, compared with city B, city A saw a 14.1% decrease in inpatient costs (P < 0.05), a 15.8% decrease in the number of inpatient discharges (P < 0.05), and an 8.3% increase in outpatient visits (P < 0.05).

Conclusions The DIP payment method promotes optimization of the medical service structure. It effectively suppresses the behavior of "rushing points" and helps to promote the diversion of mild patients to outpatient clinics, while it is still necessary to prevent unreasonable outpatient transfer.