Psychometric properties of the Depression Anxiety Stress Scales (DASS) in clinical samples.

The psychometric properties of the Depression Anxiety Stress Scales (DASS) were evaluated in two studies using large clinical samples (N = 437 and N = 241). In Study 1, the three scales comprising the DASS were shown to have excellent internal consistency and temporal stability. An exploratory factor analysis (principal components extraction with varimax rotation) yielded a solution that was highly consistent with the factor structure previously found in nonclinical samples. Between-groups comparisons indicated that the DASS distinguished various anxiety and mood disorder groups in the predicted direction. In Study 2, the conceptual and empirical latent structure of the DASS was upheld by findings from confirmatory factor analysis. Correlations between the DASS and other questionnaire and clinical rating measures of anxiety, depression, and negative affect demonstrated the convergent and discriminant validity of the scales. In addition to supporting the psychometric properties of the DASS in clinical anxiety and mood disorders samples, the results are discussed in the context of current conceptualizations of the distinctive and overlapping features of anxiety and depression.