271412 Improving the Performance of Claims-Based Comorbidity Measures in Predicting In-hospital Mortality

Wednesday, October 31, 2012

Yu-Tseng Chu, MS , Institute of Health Policy and Management, College of Public Health, National Taiwan University, Institute of Health Policy and Management, College of Public Health, National Taiwan University, Taipei, Taiwan
ShiaoChi Wu, PhD , Institute of Health and Welfare Policy, School of Medicine, National Yang-Ming University, Taipei, Taiwan
Background: Comorbidity is an important controlling factor in health services research using administrative data. Our aim was to improve the performance of various claims-based comorbidity measures in predicting in-hospital mortality.

Methods: Five different comorbidity measures, including three different adaptations of the Charlson comorbidity index (CCI), one method developed by Elixhauser et al., and the Chronic Disease Score (CDS), were selected for investigation in this retrospective cohort study. New empirical weights were derived from Cox's regression models of all inpatients in 2001. The performance of comorbidity methods with new weights was validated and compared using the c-statistics derived from multiple logistic regression models among each of the following inpatients in 2002: AMI (n=8,961), type 2 DM (n=32,687), and CHF (n=15,972).

Results: We derived new weights for five comorbidity measures from 1,214,014 inpatients in 2001. For all the adaptations of CCI, some comorbid conditions had smaller weights than the original weights, such as rheumatologic disease, ulcer disease, hemiplegia or paraplegia, and AIDS, while dementia had larger weight than the original. The empirically derived weights of the CCI and the Elixhauser method outperformed than the methods with the original definition among each of study populations in 2002.

Conclusions: The findings of this study have indicated that CCI should be reassessed in cohorts with larger sample size. The empirically derived weights of CCI performed better than the original one, and suggest that the new weights should be used in further researches.

Learning Areas:
Basic medical science applied in public health
Chronic disease management and prevention

Learning Objectives:
1.Compare different claims-based comorbidity measures. 2.Define new weights of the comorbidity measures.

Keywords: Co-morbid, Methodology

Presenting author's disclosure statement:

Qualified on the content I am responsible for because: I am responsible for the study design, data analysis, and manuscript writing. Among my scientific interests has been the epidemiology and medical care utilization. I am a PhD student in institute of health policy and management.
Any relevant financial relationships? No

I agree to comply with the American Public Health Association Conflict of Interest and Commercial Support Guidelines, and to disclose to the participants any off-label or experimental uses of a commercial product or service discussed in my presentation.