Depression, Anxiety and Stress Scales (DASS-21): Factor structure, reliability, invariance and validity of the Catalan Version

Abstract

The aim of this study was to analyse the evidence of validity, invariance and reliability of the Catalan version of the 21-item Depression, Anxiety and Stress Scale (DASS-21), using the confirmatory factor analysis (CFA) and exploratory structural equation modelling (ESEM) approach. Then, to reassess the best structure obtained in a different validation sample. The items tested correspond to those in the original version of the DASS-21, after transcultural adaptation. The questionnaire was applied to a non-clinical sample of adults (n= 716), of both sexes and a mean age of 40.94 years (SD= 15.21). For study, the sample was randomly-split into two groups: calibration sample, and cross-validation sample. In first subsample nine models were tested. As the first-order three-factor CFA model was the most parsimonious, with well-defined factors that were also supported in terms of their reliabilities (α and ω) and validities, it was selected as the preferred model. The invariance between genders was tested using the total sample. Considering all findings, the Catalan version of DASS-21 is invariant, reliable and shows construct validity, making it a suitable instrument for use in research in the Catalan adult population.