This study presents an independent replication and extension of psychometric evidence supporting the Theory of Mind Inventory (ToMI). Parents of 20 children with ASD (4; 1–6; 7 years; months) and 20 with typical development (3; 1–6; 5), rated their child’s theory of mind abilities in everyday situations. Other parent report and child behavioral assessments included the Social Responsiveness Scale-2, Vineland Adaptive Behavior Scales-2, Peabody Picture Vocabulary Test-4, and Clinical Evaluation of Language Fundamentals-Preschool, 2. Results revealed high internal consistency, expected developmental changes in children with typical development, expected group differences between children with and without ASD, and strong correlations with other measures of social and communication abilities. The ToMI demonstrates strong psychometrics, suggesting considerable utility in identifying theory of mind deficits in children with ASD.
