Translation and validation of the walking impairment questionnaire in Brazilian subjects with intermittent claudication.

BACKGROUND The Walking Impairment Questionnaire (WIQ) has been used to evaluate walking impairment in subjects with intermittent claudication (IC). However, this questionnaire has yet to be translated to Brazilian Portuguese, which limits its use in Brazilian subjects. OBJECTIVE To translate and analyze the validity and reliability of WIQ in Brazilian subjects with IC. METHODS Forty-two patients with IC, determined by the ankle-brachial index < 0.90, participated in the study. After translation and re-translation, carried out by two independent translators, the construct validity of the WIQ was analyzed by correlating the WIQ scores with the Medical Outcome Study Questionnaire Short Form 36 (SF-36) scores and the physical fitness performance (treadmill and strength tests). The reliability was analyzed with a 7-day interval between two questionnaire applications. RESULTS Significant correlations between the WIQ domains and the SF-36 (functional capacity, physical aspects, bodily pain and emotional aspects) and physical fitness performance (treadmill and strength tests) were observed. Moreover, the intraclass coefficient correlation ranged from 0.72 to 0.81, and there were no differences in WIQ scores between the two questionnaire applications. CONCLUSION The Brazilian Portuguese version of the WIQ is valid and reliable to be used in Brazilian subjects with IC.