Construct validation of the hospital anxiety and depression scale with clinical populations

Objective: The hospital anxiety and depression scale (HADS) attempts to mea sure anxiety and depression without confounding by somatic symptoms of phys ical disorder, and is widely used for this purpose. This paper addresses th ree questions about the validity of the HADS concerning its independence of physical symptoms, the extent to which its items robustly measure the iden tified constructs with varying clinical populations and situations, and its capacity to differentiate anxiety and depression. Methods: Data from patie nts with breast disease, myocardial infarction (MI), and stroke were examin ed using factor analytic and psychometric analyses. Results: Using explorat ory factor analysis in patients with breast disease, 13 of the 14 HADS item s fell on a psychological factor and loadings on the psychological factor w ere higher than loadings on the somatic factor for all items. The HADS show ed high levels of internal consistency and there was little evidence that r emoving items would improve it. Confirmatory factor analyses (CFA) in MI an d stroke groups confirmed the separation of anxiety and depression. Analyse s indicated items, which were performing poorly for these clinical groups. Conclusions: There was support For the validity of the HADS for all three q uestions. However, there were some evidences of individual items performing poorly. Given the ease of administration and the acceptability of this mea sure to ill or weak respondents, the HADS continues to perform satisfactori ly. (C) 2000 Elsevier Science Inc. All rights reserved.