TRADUÇÃO, ADAPTAÇÃO TRANSCULTURAL E VALIDAÇÃO DO LOWER LIMB FUNCTIONAL INDEX COM 10 ITENS (LLFI-10) PARA BRASILEIROS COM LESÕES OSTEOMIOARTICULARES NOS MEMBROS INFERIORES

Abstract

Objective: To translate, cross-culturally adapt, and validate the 10-item Lower Limb Functional Index (LLFI-10) for Brazilians with osteomyoarticular injuries in the lower limbs. Methods: This is a questionnaire validation study. The study consisted of translation and cross-cultural adaptation of the LLFI-10, testing of the pre-final version of the adapted version of the LLFI-10 into Brazilian Portuguese, and validation of the final version of the LLFI-10 cross-culturally adapted into Brazilian Portuguese. Data collection was performed online, in which social media posts were used. In addition, in order to ensure the validity of the construct, the Lower Extremity Functional Scale (LEFS) and the Numeric Pain Rating Scale (NPS) were used. In the statistical analysis, mean and standard deviation (quantitative data) or number and percentage (qualitative data) were used for descriptive data. Test-retest reliability was assessed using the intraclass correlation coefficient (ICC). Two measures were used to assess the error inherent in the assessment procedure: standard error of measurement (SEM) and minimum detectable difference (MDD). To determine the validity of the construct, Spearman's correlation coefficient (rho) was used to determine the magnitude of correlation between the LLFI-10, the LEFS and the NPS. For the validity of the structure, exploratory factor analysis (EFA) was used with implementation of parallel analysis to identify the number of LLFI-10 domains. The floor and ceiling effects were also assessed, being considered adequate when less than 15% of the sample. Results: A total of 110 participants were included. Most of the sample was composed of single women with knee injuries, mainly patellofemoral pain. We tested the structure with one domain (functionality) of the LLFI-10 via EFA and identified an adequate structure with Kaiser-Meyer-Olkin (KMO) test = 0.91 and p value < 0.001 in Bartlett's sphericity test. The instrument construct is valid, given that we identified a correlation magnitude greater than 0.50 with the LEFS (similar construct) and between 0.30 and 0.50 with the NPS (related construct). The reliability with an ICC value of 0.90 and the internal consistency with a Cronbach's alpha value of 0.89, with no floor or ceiling effects. Conclusion: The Brazilian version of the LLFI-10 is a valid and reliable measure to assess the functionality of the lower limbs in patients with osteomyarticular disorders.