Cross-cultural adaptation of the Zurich Claudication Questionnaire. Validation study of the Spanish version

Background. In the last few years, instruments that measure outcomes and quality of life as perceived by the patient have become tools of great clinical value. The Zurich Claudication Questionnaire is one of the main instruments for the assessment of patients suffering from lumbar spinal stenosis. Nonetheless, no valid version has been published for use in the Spanish population. Methods. The Zurich Claudication Questionnaire was translated and cross-culturally adapted to Spanish and the psychometric characteristics of the new version were then studied. Seventy-six patients were selected who were to undergo epidural steroid injection or were seen in the Hospital Complex of Navarre Spinal Unit. Results. The Spanish version of the Zurich Claudication Questionnaire shows high Cronbach alpha internal consistency values, high reproducibility, a good correlation with the most important low back condition questionnaires used worldwide and good sensitivity for detecting clinical change in patients who undergo epidural steroid injection. Conclusion. This study resulted in a version of the Zurich Claudication Questionnaire or Swiss Spinal Stenosis Questionnaire translated and cross-culturally adapted to Spanish, with highly reliable, valid and sensitive psychometric characteristics. These proven properties make the Zurich Claudication Questionnaire available for the Spanish population, to evaluate outcomes and health status as perceived by patients with spinal stenosis and claudication syndrome.