OBJECTIVES: The impact of diagnosis-related groups (DRGs) payment on quality of healthcare has been controversial and that on rational use of antibiotics has been unclear. The aim of this study was to evaluate the effect of DRG payment compare with fee for service (FFS) payment on the rational use of antibiotics in hospitals.

METHODS: Quasi-experiment with difference-in-differences (DID) analysis method was employed to evaluate the impact of a pilot reform of DRGs payment compared with FFS payment on antibiotics use in Sichuan southwest China. We extracted hospital drug consumption data of 50 secondary and tertiary hospitals in experimental and control cities in Sichuan province from 2016 to 2020, and calculated the WHO antibiotics Access, Watch, Reserve (AWaRe) classification indicators, which reflected the consumption patterns of antibiotics in included hospitals.

RESULTS: Compared with FFS payment, the DRGs payment reform had no significant impact on the total volume or expenditure of hospital antibiotic use. However, DRGs payment led to a significant reduction of -21% (p<0.01) in the proportion of Access antibiotic usage volume and an average reduction of -15% (p<0.01) in the proportion of Access antibiotic usage expenditure, and an increase of 20% (p<0.05) in the proportion of Watch antibiotic usage volume. DRGs payment reform also lead to a -0.46 (p<0.1) decrease in Access-to-Watch index as regard to volume of antibiotics expenditures. Subgroup analyses revealed that the impact of the DRGs payment reform was greater on tertiary hospitals than on secondary hospitals.

CONCLUSIONS: The transition to DRGs payment from FFS payment may have negative impact on structural rational use of antibiotics in hospitals. Close monitoring and interventional strategies are warranted to mitigate or improve rational use of antibiotics during the transition.