Cross-cultural adaptation and validation of the Foot and Ankle Outcome Score (FAOS) into Spanish (Chile)

Purpose: To adapt and validate the English version of the Foot and Ankle Outcome Score (FAOS) into Spanish FAOS-CL, following the WHO guidelines. Methods: A cross-sectional study including 318 outpatients with non-traumatic conditions. Validity, acceptability and internal consistency including correlations with the Medical Outcome Study Short Form 36 are reported. Results: The preliminary version resulted from the forward and back-translation and a pilot administration. Validation response rate was 99.22%. Substantial ceiling effects were observed for Symptoms and ADL and floor effect for QoL sub-scales. The FAOS-CL had excellent internal consistency (Cronbach's a=0.98). The principal component analysis gave five factors explaining the 72.6% of the variance. The FAOS-CL items significantly correlate with their sub-scales. FAOS-CL sub-scales significantly correlated with SF-36 components and subcomponents. Conclusion: The first Spanish version of the FAOS was generated. Culturally adapted and validated with high reliability capable of evaluating different foot and ankle conditions. (C) 2019 European Foot and Ankle Society. Published by Elsevier Ltd. All rights reserved.