Brazilian version of the ACTIVLIM: translation, cultural adaptation, and validation for neuromuscular disorders

The Activity Limitation Measure (ACTIVLIM) is a self-reported instrument consisting of 22 daily activity items graded on 3 levels (easy, difficult, or impossible).To translate, culturally adapt, and validate the Brazilian Portuguese version of the ACTIVLIM for individuals with neuromuscular disorders.The present was a cross-sectional observational study. The translation process followed standardized guidelines, including steps such as forward translation, synthesis, back-translation, expert committee review, and pretesting (psychometric analysis). A total of 268 individuals with neuromuscular disorders filled out the Brazilian ACTIVLIM. Test-retest reliability was assessed in a subgroup of 60 participants, who were evaluated twice by the same physiotherapist with an interval of one month.The intraclass correlation coefficient (ICC) for intrarater reliability was of 0.95. Internal consistency was high (Cronbach's alpha = 0.940). External validity showed strong correlations involving ACTIVLIM scores and the scores on the Vignos scale (r = -0.907), the Brooke scale (r = -0.908), and the Functional Independence Measure (r = 0.864), all with p < 0.001. Proximal muscle strength in the upper (r = 0.748) and lower limbs (r = 0.793), measured through the Medical Research Council scale, also correlated significantly with ACTIVLIM scores. Linear regression identified that the scores on the Vignos (R² = 0.8236), and Brooke scales (R² = 0.8132), as well as proximal muscle strength in the lower (R² = 0.6480) and upper limbs (R² = 0.5805), were the main predictors of ACTIVLIM variance.The Brazilian Portuguese version of the ACTIVLIM demonstrated strong reliability and validity. Its scores were significantly associated with disability level, functional independence, and muscle strength in individuals with neuromuscular disorders.