Development and psychometric performance of the French language version of the Manchester-Oxford Foot Questionnaire (MOXFQ)

Background: The Manchester-Oxford Foot Questionnaire (MOXFQ) is a 16-item patient-reported outcome measure (PROM) validated for use in patients with foot and ankle pathologies. It contains three sub-scores for pain, walking/standing and social interaction dimensions. The aim of this study was to develop a French language version of the MOXFQ and to assess its psychometric properties in patients affected by foot and ankle pathologies. Methods: According to guidelines, forward and backward independent translations were performed. The final French version was pre-tested in 45 patients. The French MOXFQ and the Short-form 36 Health Survey (SF-36) were filled in by 149 patients. A retest was performed in 39 patients. Internal consistency and test-retest reliability were assessed using Cronbach's alpha and intraclass correlation coefficient (ICC), respectively. Construct validity was assessed by factor analysis, and through correlations of MOXFQ scales with SF-36 scales. Results: Internal consistency coefficients were high with Cronbach's alpha ranging from 0.79 and 0.94. Test-retest ICCs were between 0.74 and 0.93. No floor or ceiling effects were observed. The correlations between French MOXFQ and French SF-36 subscales were moderate ranging from -0.33 to -0.71. Conclusions: The French translation of the MOXFQ revealed good psychometric properties. Our French version proved to be a reliable instrument which can be used for evaluation of patients with foot and ankle disorders. (C) 2019 European Foot and Ankle Society. Published by Elsevier Ltd. All rights reserved.