RESUMO
OBJECTIVE: This study aimed to develop the Brazilian instrument for assessing eating disorders in children and adolescents and test its psychometric quality using item response theory (IRT). DESIGN: Cross-sectional study. PARTICIPANTS: Participants aged between five and twelve years old of both sexes. MAIN MEASURES: IRT logistic model of two parameters was used to evaluate the item's severity and discrimination and test information curve of symptoms of eating disorders' latent trait symptoms. Content validity and reliability were also assessed. The IRT evaluation suggested that the instrument contained items that performed differently concerning severity, discrimination, and test information curve presented good accuracy. RESULTS: There was agreement on the clarity of language (83.3%) and theoretical relevance (91.7%), indicating good content validity. The value of the Cronbach's Alpha was 0.63 (95% confidence interval), and the result of the Spearman-Brown test was 0.65. CONCLUSION: These results indicate good performance of the screening tool in assessing the level of eating disorders in children and adolescents.