Development and validation of the brief-satisfaction with appearance scale for systemic sclerosis.

OBJECTIVE: Body image concerns are understudied in systemic sclerosis (SSc; scleroderma). The objective was to develop and cross-validate a brief version of the Satisfaction with Appearance Scale (SWAP) in order to reduce item redundancy, increase SSc relevancy, and improve the feasibility of body image assessment in SSc.
METHODS: Female patients with SSc in a development sample (Johns Hopkins Scleroderma Center) and a validation sample (Canadian Scleroderma Research Group Registry) completed the 14-item SWAP. Items for the 6-item Brief-SWAP were selected based on theoretical considerations and psychometric data from the development sample. In both samples, internal consistency reliability, convergent validity, and the hypothesized 2-factor structure (perceived social impact and subjective dissatisfaction) were compared between the Brief-SWAP and SWAP.
RESULTS: Two hundred seventeen women from the development sample and 654 women from the validation sample completed the SWAP. Cronbach's alpha for the Brief-SWAP was 0.82 in both samples, compared with 0.90 and 0.91 for the full SWAP. Correlations between the Brief-SWAP and SWAP were 0.94 and 0.95 in the development and validation samples, respectively. All correlations of the Brief-SWAP and SWAP with measures of convergent validity were substantively equal with no statistically significant differences in either sample. Based on confirmatory factor analysis, model fit for the Brief-SWAP was good in the development (χ2 [4]=9.0, comparative fit index [CFI]=0.99, Tucker-Lewis Index [TLI]=0.99, root mean square error of approximation [RMSEA]=0.07) and validation samples (χ2 [4]=19.5, CFI=0.99, TLI=0.99, RMSEA=0.08) and better than for the SWAP.
CONCLUSION: The Brief-SWAP is a reliable and valid measure of body image dissatisfaction and social discomfort in SSc that is shorter and more feasibly implemented than the SWAP.