An observational study using a national administrative database to determine the impact of hospital volume on compliance with clinical practice guidelines

Background: Little information is available on the relationship between hospital volume and compliance with clinical practice guidelines (CPGs). Objectives: To investigate the relationship between hospital volume and compliance with CPGs using a Japanese administrative database. Design and Subjects: This was an observational study that included 60,842 patients with acute cholangitis from 829 hospitals in Japan. Measures: Hospital volume was categorized into the following 3 groups based on the number of cases of acute cholangitis during the study period: low-volume hospitals (LVHs; n = 20,869), medium-volume hospitals (MVHs; n = 18,387), and high-volume hospitals (HVHs; n = 21,586). We further collected patient data with regard to CPGs for acute cholangitis, and counted the number of recommendations that had been complied with for each patient. CPGs compliance score was defined as the rate of compliance with these recommendations for each patient (range, 0-10). Aggregated CPGs compliance score was measured according to hospital volume. Results: Mean CPGs compliance score in HVHs was significantly higher than that in MVHs and LVHs (6.8 ± 1.6 vs. 5.6 ± 1.5 vs. 3.9 ± 1.4, respectively; P < 0.001). Multiple linear regression analysis revealed that hospital volume was most significantly associated with CPGs compliance score. The standardized coefficient for CPGs compliance score in HVHs was 0.689, whereas that of MVHs was 0.366 (P < 0.001). Conclusions: This study demonstrated that hospital volume was significantly associated with compliance with CPGs and that the Japanese administrative database was a viable tool for the monitoring of compliance with CPGs.