Validity and reliability of charlson comorbidity index (CCI) among iranian community-dwelling older adults

Abstract

Comorbidity Index (CCI) is a simple method for the demonstration of comorbidity burden. This study aimed to assess the validity and reliability of the CCI among Iranian community-dwelling older adults. This cross-sectional study was carried out on a sample of 600 community-dwelling older adults aged 60 years and over in Tehran, Iran, 2017. A multistage clustered random sampling method was employed to obtain the sample. The CCI consisted of 17 categories of diseases, as a means of measuring one-year illness risks and their burden. The criterion validity was assessed with Self-Rated Health (SRH) and Activities of Daily Living (ADL) scale. To test the validity and reliability of the CCI, Spearman's rho correlation and the Intra-class Correlation Coefficient (ICC) were applied using SPSS version 23 software, respectively. Out of 600 respondents, 64.0% were female. The sample mean age was 76.82 (SD = 7.45) years, and nearly 63% were married. The results of criterion validity using multiple linear regression analysis showed that the CCI was significantly predicted by SRH (Beta = -0.26, p < 0.001) and ADL (Beta = -0.17, p < 0.001). Additionally, the reliability of the CCI, using the Intra-class Coefficient Correlation, was found to be 0.77; 95% CI, 0.60 to 0.87. As the results showed a good level of validity and reliability of the CCI, its use is therefore suggested in health surveys among Iranian community-dwelling older adults.