The Derriford Appearance Scale (DAS-59): A new scale to measure individualresponses to living with problems of appearance

Objectives. To develop a reliable and valid self-report scale which (1) wil l assess the distress and difficulties experienced in living with a problem of appearance; (2) can be used with clinical and non-clinical populations; and (3) facilitates clinical decisionmaking and research through good stan dardization, sensitivity and discrimination. Design. Cross-sectional survey designs using clinical and non-clinical popu lations and a pre-post intervention design using plastic surgery patients. Method. A large initial item set was refined through a controlled pre-post surgery study and a cross-sectional study of a plastic surgery waiting list (606). The resulting 59-item scale was administered to 1740 patients with problems of appearance and to a representative general population sample (1 001). Results. Principal component and factor analyses identified a stable live-f actor structure accounting for 63.5% of the variance, with a primary factor of self-consciousness of appearance, internal consistency was high (alpha = .98) and test-retest reliabilities (three months) were good (.75 (general population);.86 (patients)). Correlations with existing rests showed appro priate criterion validity (.74-.62). Good construct validity was evidenced in pre- and post-operative changes, in differences between patients and con trols and in convergent and divergent correlation patterns. The general pop ulation data reveal widespread concerns about appearance. Conclusions. The DAS-59 provides a widely acceptable, psychometrically robu st, factorial self-report scale to assess distress and dysfunction in probl ems of appearance across the full range of 'visibility' and aetiologies. It is sensitive to therapeutic change and discriminates well between patient groups.