Validation of the Walking Impairment Questionnaire for Spanish patients

Abstract

Background: The Walking Impairment Questionnaire (WIQ) is a short, easy to complete, disease-specific questionnaire to assess intermittent claudication. A Spanish version of the WIQ for Hispanic Americans has recently been validated in Texas, but it needs to be validated for European Spanish people. Patients and methods: After translation and cultural adaptation of the WIQ, 920 patients with intermittent claudication (ankle brachial index < 0.9) completed two questionnaires (Spanish version of the WIQ and European Quality of Life 5 Dimension [EQ-5D]). The validity of the WIQ was determined by correlating WIQ and EQ-5D. Test-retest reliability and internal consistency were determined using the intra-class correlation coefficient (ICC) and Cronbach’s alpha, respectively. Results: The three domains of the WIQ were moderately correlated with the EQ-5D health outcome (r = 0.54 to 0.60; p < 0.001). Test-retest reliabilities ranged from ICC = 0.89 to 0.91 and internal consistency (Cronbach’s alpha = 0.92) was high. Conclusions: The Spanish version of the WIQ for European Spanish patients was valid and reproducible, suggesting that it could be used in Spanish patients with intermittent claudication.