Translation, cultural adaptation, and validation of the American Orthopaedic Foot and Ankle Society (AOFAS) hallux metatarsophalangeal–interphalangeal scale into Portuguese

Abstract

INTRODUCTION: Effective questionnaires are required in clinical trials to validate the outcomes of orthopedic surgery. Many questionnaires are available only in English and require linguistic and cultural adaptation so that researchers can use them accurately. This study aimed to translate and culturally adapt the American Orthopaedic Foot and Ankle Society (AOFAS) Hallux Metatarsophalangeal–Interphalangeal Scale into Portuguese and assess its reproducibility. EXPERIENCE OR INTERVENTION REPORT: Translation and cultural adaptation followed the criteria proposed by Reichenheim and Moraes, ensuring methodological rigor. Fifty patients with hallux disorders were selected and completed the AOFAS questionnaire and SF-36 at two separate time points. The collected data were used to assess the internal consistency and reproducibility of the translated version. Statistical analysis included Cronbach’s alpha, Spearman’s correlation, and interobserver agreement. DISCUSSION: The results demonstrated excellent internal consistency (Cronbach’s alpha=0.99) and high reproducibility, with very similar values between the two administrations (65.5 and 64.2), as well as high agreement between raters (65.5 vs 65.3). Spearman’s correlation was also extremely high (1.0), indicating strong reliability. This experience reinforces the importance of rigorous processes when adapting clinical instruments and confirms that the translated AOFAS questionnaire is applicable to the Brazilian context, supporting its safe use in research and clinical practice.