Factor structure and longitudinal invariance of the Center for Epidemiological Studies Depression Scale (CES-D) in adult women: application in a population-based sample of mothers of children with epilepsy.

The objective of this study was to examine the factor structure and longitudinal measurement invariance of the Center for Epidemiological Studies Depression Scale (CES-D). The population-based sample included 347 adult women who had children participating in the Health-related Quality of Life in Children with Epilepsy Study. Longitudinal confirmatory factor analysis was used to confirm the factor structure and test for measurement invariance. The original CES-D four-factor model (depressed affect, positive affect, somatic activity, and interpersonal relations) provided the best fit to the data compared to alternate models: [χ(2) = 362.95 (df = 164); Comparative Fit Index (CFI) = 965; Tucker-Lewis Index (TLI) = 0.960; Weighted Root Mean Square Residual (WRMR) = 0.966; Root Mean Square Error of Approximation (RMSEA) = 0.059, 90% confidence interval (CI), 0.051, 0.068] and was used for invariance testing. Results suggested full measurement invariance over time with the final model demonstrating adequate fit [χ(2) = 2303.92 (df = 1,776); CFI = 0.957; TLI = 0.952; WRMR = 1.149; RMSEA = 0.033, 90% CI, 0.030, 0.038]. We conclude that the four-factor structure of the CES-D is supported for adult women and that the measurement of the scale is longitudinally invariant. Clinicians and researchers can be confident that longitudinal changes in CES-D scores reflect true changes in depressive symptomatology and are not an artifact of changes in the interpretation of items in the scale over time.