The psychometric properties of a self‐report inventory of autistic symptoms in individuals with autism spectrum disorder

Introduction and Methods: This study examined 85 parental‐reports with 85 self‐reports of autistic symptoms with the 84‐item Coolidge Autistic Symptom Survey (CASS). The CASS covers all of the diagnostic criteria for autism spectrum disorder (ASD) in the Diagnostic and Statistical Manual of Mental Disorders (DSM‐5), as no studies to date have compared the self‐reports of individuals with autism with parent‐ or significant‐other‐reports of those individuals using the complete DSM‐5. Results: The CASS‐Parental‐Report and CASS‐Self‐Report exhibited excellent internal reliability (α = 0.97 and 0.96, respectively). There was support for the hypothesis that parental‐reports and self‐reports would be similar (r = 0.66, p