Cross-cultural adaptation of the Ritvo Autism Asperger Diagnostic Scale-Revised (RAADS-R) to Brazilian Portuguese (RAADS-R-BR)

This study details the cross-cultural adaptation of the Ritvo Autism Asperger Diagnostic Scale-Revised (RAADS-R) to Brazilian Portuguese (RAADS-R-BR). The adaptation process involved translation, synthesis, expert review (n = 5), back-translation, validation by the original author, and a pilot study (n = 142) with autistic adults aged 19–60 (M = 33.49, SD = 8.44). Data collection was conducted via Google Meet by trained assistants. Confirmatory Factor Analysis (CFA) evaluated the instrument’s structure using indices like CFI, TLI, RMSEA, and SRMR. Internal consistency was measured through Cronbach’s α, McDonald’s ω, and CR, with item parameters analyzed using IRT. Semantic equivalence was maintained, showing satisfactory coefficients for CL (0.89), PP (0.87), and RL (0.88), and participant comprehension above 80%. CFA revealed 27 items with non-significant factor loadings in both four-factor and two-factor models, indicating structural limitations. The RAADS-14 screen model had excellent fit indices [χ²(74) = 88.072, p = 0.126], though items Q60 and Q30 were not significant. Results indicate weak performance in analyses using Classical Test Theory and Item Response Theory. Future research should revise problematic items and consider creating a shortened version of RAADS-R-BR with items showing satisfactory discrimination.