The Evidence-Based Instrument for the Nutritional Assessment of Individuals with Autism Spectrum Disorder

Background: Autism spectrum disorder (ASD) presents diverse challenges that significantly impact feeding, nutrition, growth, and development. The heterogeneity of ASD manifestations adds complexity to assessments due to the broad range of factors to be considered. Moreover, the literature lacks a comprehensive tool specifically addressing nutritional aspects in ASD. Methods: Conducted in two steps, this study first involved researchers selecting evidence-based elements related to ASD and nutrition to develop a preliminary tool. Content validation was subsequently undertaken using a modified Delphi method, whereby expert consensus was sought from 30 dietitians with experience in ASD, who evaluated the tool through a digital questionnaire. Four quality criteria were evaluated: functionality, organization, language and comprehensibility, and comprehensiveness. Results: Levels of strong agreement with the quality criteria ranged from 63.3% to 80%, specifically functionality (76.7%), organization (73.3%), language and comprehensibility (80%), and comprehensiveness (63.3%). Thematic analysis highlighted six key areas for improvement. The instrument assesses nutritional aspects across seven domains: life history, food-related aspects, feeding behavior, dietary intake, daily routines, clinical aspects, and anthropometry. Conclusions: This is the first known tool to comprehensively address the nutritional needs of individuals with ASD, offering a detailed framework for clinical application. It supports initial assessments, ongoing monitoring, and targeted interventions, supporting dietitians worldwide in clinical decision-making.