Measuring disability in subjects with anxiety disorders

Subjects with anxiety disorders display substantial disabilities in health-related quality of life. The Sheehan Disability Scale (SDS) and SF-36 Questionnaire (SF-36) have been administered to subjects with anxiety disorders participating in psychopharmacology clinical trials and observational studies to evaluate their impaired functioning. The SDS does not address and does not include all the disabilities important to subjects with anxiety disorders and susceptible to being affected by drugs with anxiolytic effects, all of which are associated with significant problems. As a single-state-in-time rating, the SDS is often inadequate to discern subtle, but important,changes which may occur between measurements. The SF-36 as a measure of health status can, on the other hand, assess only the patient's behavior most directly affected by the disorder and treatment. As a result, the SF-36 enables the differentiation of functioning and well-being of subjects with anxiety disorders from diverse populations. There is little documentary evidence that demonstrates the value and actual performance of the SDS and SF-36 for the intended purpose. In the absence of a general consensus concerning operational definition, the measurement of disability in this patient population with these scales may be obsolete. There is the need for more specific and simple instruments capable to assess the distinct pattern of impairment associated with subjects with anxiety disorders.