Anxiety, Depression, HADS, CVD
OBJECTIVE: The Hospital Anxiety and Depression Scale (HADS) is a prolifically used scale of anxiety and depression. The original bidimensional anxiety-depression latent structure of the HADS has come under significant scrutiny, with previous studies revealing one-, two-, three- and four-dimensional structures. The current study examines the latent structure of the HADS using a non-parametric item response theory method. METHOD: Using data conglomerated from four independent studies of cardiovascular disease employing the HADS (n=893), Mokken scaling procedure was conducted to assess the latent structure of the HADS. RESULTS: A single scale consisting of 12 of 14 HADS items was revealed, indicating a unidimensional latent HADS structure. DISCUSSION: The HADS was initially intended to measure mutually exclusive levels of anxiety and depression; however, the current study indicates that a single dimension of general psychological distress is captured.
Cosco TD, Doyle F, Ward M, McGee H. Mokken scaling analysis of the Hospital Anxiety and Depression Scale in individuals with cardiovascular disease. General Hospital Psychiatry. 2011 Dec 14. [Epub ahead of print]