Translation and validation of MIDAS for Brazilians

Background and objective: The Migraine Disability Assessment (MIDAS) is a widely used tool for evaluating disability associated with migraines. However, although a translated version exists in Brazil, its adaptation did not follow the methodological standards recommended by guidelines. Therefore, this study aimed to translate and validate MIDAS for the Brazilian population. Methods: This is a methodological study conducted in two stages: translation and adaptation, following the recommendations of the Professional Society for Health Economics and Outcomes Research, and measurement properties analysis, including intra-rater reliability using the Intraclass Correlation Coefficient (ICC), internal consistency with Cronbach's alpha, content validity through the Content Validity Index (CVI), criterion validity using Spearman's correlation, and content validity evaluated through the CVI based on the Consensus-based Standards for the Selection of Health Measurement Instruments (COSMIN). A total of 149 individuals participated, comprising both sexes, with a mean age of 38 ± 12 years, all diagnosed with migraine according to the ICHD-3 criteria. Results: During translation and cultural adaptation, minimal changes were made to the original MIDAS structure. The measurement properties demonstrated moderate intra-rater reliability (ICC = 0.612; 95% Confidence Interval = 0.312–0.803; F (25, 25) = 4.286; p < 0.001), internal consistency with a Cronbach's alpha of 0.655, and a weak positive correlation between MIDAS and HIT-6. The global CVI was 0.78, considered satisfactory for content validity. Conclusion: The MIDAS instrument adapted to Brazilian Portuguese is valid for measuring migraine-related disability.