| Comorbidities are diseases or conditions that co-exist with a disease of interest. The importance of comorbidities is that they alter treatments, change resource utilization and confound the results of treatment survival analysis. The objective of this study was to determine the best comorbidity index to use in survival analysis of patients with squamous cell carcinoma of the Head and Neck. Five validated indexes, with very different methodologies, including the Charlson Index, the Cumulative Illness Rating Scale, the Kaplan-Feinstein Classification, the Index of Co-existent Disease, and the Chronic Disease Scale were critically reviewed and then tested. Data from 379 unselected consecutive patients from the Kingston Regional Cancer Center with complete 3 year follow-up were used. Kaplan-Meier analysis and Cox Proportional Hazards Regression were used to stratify patients into three levels of increasing severity of comorbidity for each index The Kaplan-Feinstein Classification was the most successful in stratifying patients in this population. |
