Hospital Anxiety and Depression Scale: Factor Structure, Internal Consistency and Convergent Validity in Patients with Dizziness.

Psychiatric comorbidities, particularly anxiety-related pathologies, are often observed in dizzy patients. The Hospital Anxiety and Depression Scale (HADS) is a widely used self-report instrument used to screen for anxiety and depression in medical outpatient settings. The purpose of this study was to assess the factor structure, internal consistency and convergent validity of the HADS in an unselected group of patients with dizziness. The HADS and the Dizziness Handicap Inventory (DHI) were administered to 205 dizzy patients. An exploratory factor analysis was conducted and indicated a 3-factor structure, inconsistent with the 2-subscale structure (i.e. anxiety and depression) of the HADS. The total scale was found to be internally consistent, and convergent validity, as assessed using the DHI, was acceptable. Overall findings suggest that the HADS should not be used as a tool for psychiatric differential diagnosis, but rather as a helpful screener for general psychiatric distress in the two domains of psychiatric illness most germane in dizzy patients.