ORIGINAL ARTICLE 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 Mark A. Ferro & Kathy N. Speechley Received: 18 August 2012 / Accepted: 4 February 2013 / Published online: 19 February 2013 # Springer-Verlag Wien 2013 Abstract 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. Keywords Age . Depression . Measurement . Psychometrics Introduction Caring for a child recently diagnosed with a chronic health condition can be the source of tremendous stress for parents, particularly mothers, who most often assume the primary care- giving role in families (Gillespie and Primavera 2000). As a result, mothers may have an elevated risk for psychological distress, including depression, in response to their child’ s diag- nosis (Dolgin et al. 2007; Ferro et al. 2011b). Understanding maternal depression has important clinical implications—not only are symptoms of depression unhealthy for mothers, re- search has provided evidence showing that depression in mothers has a significant negative effect on children’ s health (Beardslee et al. 1998; Kim-Cohen et al. 2005; Pilowsky et al. M. A. Ferro Department of Psychiatry and Behavioural Neurosciences, McMaster University, Hamilton, Canada M. A. Ferro Offord Centre for Child Studies, McMaster University, Hamilton, Canada K. N. Speechley Department of Paediatrics, Western University, Commissioners Road East, Room E6-103, London, ON N6A 5W9, Canada K. N. Speechley Department of Epidemiology and Biostatistics, Western University, London, Canada K. N. Speechley Children’ s Health Research Institute, Western University, London, Canada M. A. Ferro (*) Department of Psychiatry and Behavioural Neurosciences, Offord Centre for Child Studies, McMaster University, Chedoke Site, Central Building, Room 310, 1280 Main Street West, Hamilton, ON L8S 4K1, Canada e-mail: ferroma@mcmaster.ca Arch Womens Ment Health (2013) 16:159–166 DOI 10.1007/s00737-013-0331-5