Gujarati translation, validity and reliability of Walking Impairment Questionnaire in people with intermittent claudication due to peripheral artery disease

Introduction: The Walking Impairment Questionnaire (WIQ) is a common and easy-to-use assessment of walking incapacity in people with claudication due to peripheral artery disease (PAD). It has four subscales: pain severity, walking distance, walking speed, and ability to climb stairs. It has not been translated into Gujarati, which limits its use in Indian subjects. Aim: This study aims to translate and assess the validity and reliability of a Gujarati version of WIQ. Materials and Methods: This study had three phases: 1. Forward and backward translation and Cultural adaptation of WIQ into the Gujarati language by two independent translators, 2. Face and content validation by six clinical reviewers and 10 participants with PAD and Type II diabetes, 3. Concurrent and construct validity, test-retest reliability, and internal consistency of Gujarati, the WIQ was assessed on 160 participants with PAD and Type II diabetes who had a mean Ankle Brachial Index (standard deviation) <0.40 (0.1). The concurrent and construct validity of the WIQ was analyzed by correlating the WIQ distance and speed score with 6-minute walk distance (6MWD) and speed and WIQ total score with the Medical Outcome Study Questionnaire Short Form 36 (SF-36) score using Pearson's correlation coefficient. Test-retest reliability was analyzed using an intraclass correlation coefficient (ICC) with a seven-day interval between two questionnaire applications. Internal consistency of the total WIQ score was determined using Cronbach's alpha. Results: Following translation, the Gujarati WIQ was considered acceptable and understandable by people with PAD. There was excellent correlation between the WIQ distance score and 6-minute walk test distance (r = 0.95, P < .05)) , the WIQ speed score and 6-minute walk test speed score (r = 0.89, P < .05)) and the Gujarati WIQ total score and total score of physical functioning domain of SF- 36 (r = 0.99, P < .05). There was excellent test-retest reliability over 7 days for total WIQ score (ICC = 0.94). The Cronbach's alpha for internal consistency of 0.97 for total WIQ score were excellent. This demonstrates the sufficient homogeneity of the total questionnaire. Conclusion: The Gujarati version of the WIQ is reliable and valid and can be used to assess self-reported walking impairment in Gujarati-speaking people with PAD and Type II Diabetes.