Depression, Anxiety, and Stress: How Should Clinicians Interpret the Total and Subscale Scores of the 21-Item Depression, Anxiety, and Stress Scales?

Abstract

The 21-item Depression, Anxiety, and Stress Scales (DASS-21) is a self-report measure that is easy to administer, quick to score, and is freely available. Widely used in diverse settings and populations, confirmatory factor analytic evidence has accumulated for a bifactor model underlying this multidimensional measure. Studies employing an exploratory bifactor approach to more closely examine its underlying structure and inter-relations of factors, however, have been scarce. This is unfortunate because confirmatory techniques often employ indirect ways of handling model misspecification, whereas exploratory methods enable more direct approaches. Moreover, more precise approaches to modeling an exploratory bifactor structure have not been examined with the DASS-21. Based on several large samples of undergraduate students in the United States, the first two parts of the paper (Studies 1 and 2) utilized both exploratory ( M = 19.7 years of age) and confirmatory factor analytic methods ( M = 19.7 years of age) following those presented by contemporary multidimensional modeling theorists. Building upon these results, the third part of the paper (Study 3; M = 20.0 years of age) examined sensitivity-/specificity-related indices to provide cut-off score recommendations for a revised DASS-21 instrument based on a newly identified and supported bifactor structure. Implications of these results are discussed in terms of taxonomy, challenges inherent in multidimensional modeling, and potential use of the revised DASS-21 measure as a component of an actuarial decision-making strategy to inform clinical referrals.