Exploring anxiety symptoms in a large‐scale twin study of children with autism spectrum disorders, their co‐twins and controls

These findings support previous reports of heightened anxiety in children with ASDs, at least on parent-reported measures. Unaffected co-twins of children with ASDs also showed increased anxiety, generating questions about the potential etiological overlap between ASDs and anxiety. Progress in this area now depends on more refined anxiety measurement in ASDs and continued investigation of interrater differences.