Abstract
BACKGROUND: Vestibular Activities and Participation Measure (VAP) subscales assess the effect of vestibular disorders on activity and participation. This study aimed to perform the cross-cultural adaptation and assess the validity, internal consistency, reliability, and measurement error of the Brazilian version of VAP subscales. METHODS: The cross-cultural adaptation followed the translation, synthesis, back-translation, review by a committee of experts, and pretesting phases. Structural validity was assessed using exploratory factor analysis (EFA) and confirmatory factor analysis (CFA), while Spearman's correlation between VAP subscales and the Dizziness Handicap Inventory (DHI) was used to assess construct validity. Cronbach's alpha measured internal consistency. Intraclass correlation coefficient (ICC) assessed intra- and inter-rater reliability, and measurement error was calculated by using the standard error of measurement (SEM) and minimal detectable change (MDC). RESULTS: Additional information was included in the Brazilian version of the Vestibular Activities and Participation measure (VAP-BR) after approval by one of the developers of the instrument to improve the understanding among individuals. One factor was found in the EFA for each subscale with 50% explained variance. Regarding CFA, the subscales 1 (S1) and 2 (S2) presented, respectively, adequate model fit indices (ie, comparative fit index of 0.99 and 0.97, and standardized root mean square residual of 0.04 for both subscales), but a very low factor load in item 6 of S1 (0.08). Chronbach's alpha was 0.80 (S1) and 0.82 (S2). For intra-rater assessment, the S1 and S2 presented an ICC of 0.87 and 0.90, SEM of 0.01 and 1.16, and MDC of 0.39 and 0.46, respectively. When assessed by 2 different raters, SEM values were 1.03 and 1.53, and MDC values were 2.85 and 4.23 for S1 and S2, respectively; both subscales showed an ICC of 0.92. Correlations between DHI and VAP subscales presented coefficients above 0.57. CONCLUSION: The Brazilian version of VAP subscales presents good measurement properties and may assist health professionals in identifying activity limitations and participation restrictions in individuals with vestibular disorders.