The Health Assessment Questionnaire for Spondyloarthropathies (HAQ-S) is a commonly used questionnaire to evaluate function and health status of patients with ankylosing spondylitis (AS). The objective of this study was to cross-culturally adapt the HAQ-S into Chinese and then to evaluate its reliability and validity. The Chinese version of the HAQ-S was obtained with a five-step procedure of translation and cross-cultural adaptation. All invited patients met the New York criteria for AS, and a total of 103 patients finally participated in this study. Intraclass correlation coefficient (ICC) was used to evaluate the test-retest and inter-rater reliability of the HAQ-S. Internal consistency of the questionnaire was evaluated by Cronbach's alpha coefficient. Spearman's correlation coefficient was calculated to assess the construct validity between the HAQ-S and Bath AS Disease Activity Index (BASDAI), Bath AS Functional Index (BASFI), Bath AS Metrology Index (BASMI), and the laboratory parameters (erythrocyte sedimentation rate, ESR; C-reactive protein, CRP). Test-retest and inter-rater reliability were excellent with intraclass correlation coefficients of 0.987 (p < 0.05) and 0.982 (p < 0.05), respectively. The overall internal consistency of the HAQ-S was found satisfactory (Cronbach's alpha = 0.914). The Chinese version of the HAQ-S correlated good with the BASFI (r = 0.749, p < 0.01), and moderate with the BASDAI (r = 0.581, p < 0.01) and the BASMI (r = 0.425, p < 0.01). But, the adapted questionnaire correlated poorly with ESR (r = 0.298, p < 0.01) or CRP (r = 0.283, p < 0.01). The Chinese version of the HAQ-S is reliable and valid for the evaluation of Chinese-speaking patients with AS.
Keywords: Ankylosing spondylitis; Chinese; HAQ-S; Translation; Validation.