Risk Adjustment in Outcome Assessment: the Charlson Comorbidity Index

W. D’Hoore; C. Sicotte; C. Tilquin

doi:10.1055/s-0038-1634956

Methods of Information in Medicine, Inhaltsverzeichnis

Methods Inf Med 1993; 32(05): 382-387
DOI: 10.1055/s-0038-1634956

Original Article

Schattauer GmbH

Risk Adjustment in Outcome Assessment: the Charlson Comorbidity Index

Authors

W. D’Hoore

¹Université Catholique de Louvain, Faculté de Médecine, Département des Sciences Hospitalières et Médico-Sociales, Bruxelles, Belgium
C. Sicotte

²Universite de Montreal, Département d’Administration de la Santé, Montreal, Canada
C. Tilquin

²Universite de Montreal, Département d’Administration de la Santé, Montreal, Canada

Abstract

To measure the burden of comorbid diseases using the MED-ECHO database (Quebec), the so-called Charlson index was adapted to International Classification of Disease (ICD-9) codes. The resulting comorbidity index was applied to the study of inpatient death in a group of 62,456 patients having one of the following conditions: ischemic heart disease, congestive heart failure, stroke, or bacterial pneumonia. Multiple logistic regression was used to relate inpatient death to its predictors, including gender, principal diagnosis, age, and the comorbidity index. Various transformations of the comorbidity score were performed, and their effect on predictive accuracy was assessed. The comorbidity index was constantly and strongly associated with death. When gender, age, comorbidity and the principal diagnoses were taken into account, the area under the receiver-operating curve was 0.83. Therefore, the Charlson Index is a useful approach to risk adjustment in outcomes research from administrative databases.

Key-Words

Comorbidity - Administrative Data - Risk Adjustment - Logistic Regression - Outcomes Research

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Referenzen

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