The Derriford Appearance Scale (DAS59): a new psychometric scale for the evaluation of patients with disfigurements and aesthetic problems of appearance

The DAS59 has been designed and developed to meet the need for an objective measure of the spectrum of psychological distress and dysfunction that is characteristic of disfigurements, deformities and aesthetic problems of app earance. Content validity has been assured by basing the scale's items on a detailed autobiographical study of representative patients. Internal consi stency is high (0.98) and test-retest reliabilities are good (general popul ation: 0.75; clinical population: 0.86). Correlations with other appropriat e standardised tests show good criterion validity and good construct validi ty. Factor analysis of 2741 data sets (general population and clinical popu lation) identified three factors that are not feature specific and two that are (bodily and sexual features, facial features). The DAS59 thus generate s a full-scale score and five factorial sub-scale scores. The DAS59 has bee n standardised on the clinical population across a range of patient groups and on the general population subdivided into those concerned and those not concerned about appearance. The DAS59 is highly sensitive as a measure of change following treatment with large and significant preoperative-postoper ative reductions in full-scale and factorial scores of patients treated for facial features or bodily/sexual features. The DAS59 offers benefits for p atient selection in both cosmetic and reconstructive plastic surgery and in the evaluation of outcome. It provides valid and reliable data for clinica l audit and governance and for evaluating the merits of one treatment proto col against another. (C) 2001 The British Association of Plastic Surgeons.