Department of Educational and Counselling Psychology, McGill University and Lady Davis Institute for Medical Research, Jewish General Hospital, Montréal, Québec, Canada.
Department of Psychiatry, McGill University and Lady Davis Institute for Medical Research, Jewish General Hospital, Montréal, Québec, Canada; Behavioural Science Institute, Clinical Psychology, Radboud University, Nijmegen, the Netherlands.
Body Image. 2017 Sep;22:97-102. doi: 10.1016/j.bodyim.2017.06.005. Epub 2017 Jul 13.
The Satisfaction with Appearance Scale (SWAP) has been used to assess body image distress among people with the rare and disfiguring disease systemic sclerosis (SSc); however, it has not been validated across different languages groups. The objective was to examine differential item functioning of the SWAP among 856 Canadian English- or French-speaking SSc patients. Confirmatory factor analysis was used to evaluate the SWAP two-factor structure (Dissatisfaction with Appearance and Social Discomfort). The Multiple-Indicator Multiple-Cause model was utilized to assess differential item functioning. Results revealed that the established two-factor model of the SWAP demonstrated relatively good fit. Statistically significant, but small-magnitude differential item functioning was found for three SWAP items based on language; however, the cumulative effect on SWAP scores was negligible. Findings provided empirical evidence that SWAP scores from Canadian English- and French-speaking patients can be compared and pooled without concern that measurement differences may substantially influence results.
外貌满意度量表 (SWAP) 已被用于评估患有罕见且毁容性疾病系统性硬化症 (SSc) 的人群的身体意象困扰；然而，它尚未在不同语言群体中得到验证。本研究的目的是在 856 名讲英语或法语的加拿大 SSc 患者中检验 SWAP 的差异项目功能。验证性因子分析用于评估 SWAP 的两因素结构（对外貌不满和社交不适）。多指标多原因模型用于评估差异项目功能。结果表明，SWAP 的既定两因素模型具有相对较好的拟合度。基于语言，SWAP 的三个项目存在具有统计学意义但幅度较小的差异项目功能；然而，对 SWAP 评分的累积影响可以忽略不计。研究结果提供了经验证据，表明来自讲英语和法语的加拿大患者的 SWAP 评分可以进行比较和汇总，而不必担心测量差异可能会极大地影响结果。
