Prevalence of anxiety in patients with an implantable cardioverter defibrillator: measurement equivalence of the HADS-A and the STAI-S

The Hospital Anxiety and Depression Scale (HADS-A) and State-Trait Anxiety Inventory (STAI-S) are popular instruments for assessing anxiety and are considered interchangeable, although little is known about their equivalence. Hence, we examined whether the two instruments are (i) equivalent with respect to determining the prevalence of probable clinical anxiety levels and (ii) reflect variation on a common anxiety attribute. Score and construct...