Developing a Hospital-Wide All-Cause Risk-Standardized Readmission Measure Using Administrative Claims Data in Korea: Methodological Explorations and Implications

건강보험 청구자료를 이용한 일반 질 지표로서의 위험도 표준화 재입원율 산출: 방법론적 탐색과 시사점

  • Kim, Myunghwa (Division of Health Care Management and Policy, Seoul National University Graduate School of Public Health) ;
  • Kim, Hongsoo (Division of Health Care Management and Policy, Seoul National University Graduate School of Public Health) ;
  • Hwang, Soo-Hee (Health Insurance Review and Assessment Research Institute, Health Insurance Review and Assessment Service)
  • 김명화 (서울대학교 보건대학원 보건정책관리학과) ;
  • 김홍수 (서울대학교 보건대학원 보건정책관리학과) ;
  • 황수희 (건강보험심사평가원 심사평가연구소)
  • Received : 2015.06.03
  • Accepted : 2015.09.24
  • Published : 2015.09.30


Background: The purpose of this study was to propose a method for developing a measure of hospital-wide all-cause risk-standardized readmissions using administrative claims data in Korea and to discuss further considerations in the refinement and implementation of the readmission measure. Methods: By adapting the methodology of the United States Center for Medicare & Medicaid Services for creating a 30-day readmission measure, we developed a 6-step approach for generating a comparable measure using Korean datasets. Using the 2010 Korean National Health Insurance (NHI) claims data as the development dataset, hierarchical regression models were fitted to calculate a hospital-wide all-cause risk-standardized readmission measure. Six regression models were fitted to calculate the readmission rates of six clinical condition groups, respectively and a single, weighted, overall readmission rate was calculated from the readmission rates of these subgroups. Lastly, the case mix differences among hospitals were risk-adjusted using patient-level comorbidity variables. The model was validated using the 2009 NHI claims data as the validation dataset. Results: The unadjusted, hospital-wide all-cause readmission rate was 13.37%, and the adjusted risk-standardized rate was 10.90%, varying by hospital type. The highest risk-standardized readmission rate was in hospitals (11.43%), followed by general hospitals (9.40%) and tertiary hospitals (7.04%). Conclusion: The newly developed, hospital-wide all-cause readmission measure can be used in quality and performance evaluations of hospitals in Korea. Needed are further methodological refinements of the readmission measures and also strategies to implement the measure as a hospital performance indicator.


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