Validity of the Center for Epidemiological Studies Depression Scale among Brazilian elderly

OBJECTIVE: To obtain internal construct and criteria validity for the Center of Epidemiological Studies - Depression scale in elderly people. METHODS: The instrument was applied to 903 elderly living in a city in southeastern Brazil, between 2002 and 2003. Results were compared with the Brazilian version of the CES-D applied to a sub-sample of 446 participants. Internal consistency of the two scales was assessed using Cronbach's alpha measured for the items in their total and for the items of each factor obtained for the assessed instrument. To assess the construct validity, the 20 items underwent exploratory factorial analysis to discover their variation pattern and the variance explained according to each factor. RESULTS: The scale presented satisfactory index for internal validity (alpha=0.860), sensibility (74.6%), specificity (73.6%), and for cutoff point > 11. However, it presented a relatively high frequency of false positives compared to the GDS 33.8% vs. 15%. Exploratory factorial analysis of the instrument created factorial structure with three factors: negative affects, problems initiating behaviors, and positive affects. CONCLUSIONS: The instrument seemed to be psychometrically suitable when applied to older people. However, further cross-sectional and longitudinal studies, carried out in different contexts, may explain the effects of somatic and situational variables on the results of the instrument in older people.