Cross-cultural adaptation and validation of the Brazilian version of the Scleroderma Health Assessment Questionnaire (SHAQ)

The Scleroderma Health Assessment Questionnaire (SHAQ) is a feasible multisystem specific tool that has been extensively used as an additional assessment for systemic sclerosis (SSc). The aim of this study is to cross-culturally adapt and validate the Brazilian version of the SHAQ. Construct validity was assessed based on the correlations between SHAQ and both the Medical Outcomes Survey Short Form 36 version 2 (SF-36v2 (TM)) and the Health Assessment Questionnaire Disability Index (HAQ-DI). The correlation between the SHAQ and disease severity was assessed by Spearman's correlation coefficient. The reproducibility of the SHAQ was evaluated by the intraclass correlation coefficient (ICC). Among the 151 consecutive outpatients evaluated, 59 % had limited SSc subtype. The overall disease severity visual analog scale (VAS) of the SHAQ was statistically significantly correlated to HAQ-DI, pain VAS, and the SF-36v2 (TM) physical component summary score (r = 0.595, r = 0.612, and r = -0.582, respectively; p < 0.001). Further analysis of all SF-36v2 (TM) components revealed statistically significant correlations between overall disease severity VAS and bodily pain (r = -0.621, p < 0.001), vitality (r = -0.544, p < 0.001), physical function (r = -0.510, p < 0.001), and role limitation-physical dimensions (r = -0.505, p < 0.001). Moreover, digestive, pulmonary, and overall disease severity VASs were statistically significantly correlated to the number of organs involved (r = 0.178, p = 0.029; r = 0.214, p = 0.008; r = 0.282, p < 0.001). We also demonstrated high reproducibility for SHAQ (ICC = 0.757, 95 % confidence interval = 0.636-0.842). The Brazilian version of the SHAQ demonstrated both construct and discriminant validities as well as good reproducibility.