Abstract
BACKGROUND/AIMS: The psychometric properties of Center for Epidemiological Studies Depression Scale (CES-D) have never been substantively investigated in caregivers of persons with dementia (PwD). We evaluated the validity and reliability of CES-D for detecting caregiver depression in dementia, and assessed whether CES-D could provide added utility beyond Zarit Burden Interview (ZBI). METHOD: Family caregivers of community-dwelling PwD (n = 394) completed self-administered questionnaires containing CES-D. Factorial validity was evaluated with confirmatory factor analysis; convergent and discriminant validity with Pearson's correlation coefficient; known-group validity by comparing across key variables; and internal consistency reliability with Cronbach's α. Cohen's κ was used to compare the agreement between those with depression (CES-D ≥16) and those with high caregiver burden (ZBI >60). RESULTS: CES-D demonstrated convergent, discriminant and known-group validity, consistent with a priori hypotheses. The original four-factor model of CES-D produced the best model-fit indices. Internal consistency reliability was good for the CES-D total scale (α = 0.92), but lower for the Positive affect and Interpersonal problems subscales (α = 0.70-0.74). Forty-five percent of the caregivers had depression as identified by CES-D (95% CI 40-50%), but most of them were not identified by high ZBI scores (κ = 0.16). CONCLUSIONS: CES-D is a valid and reliable scale for detecting caregiver depression in dementia. It has added utility, beyond that of a caregiver burden scale, in identifying a subgroup of caregivers with depression but not burden. However, two subscales (Positive affect and Interpersonal problems) may require caution in interpretation among non-Caucasian caregivers.