Diagnostic assessment in a sample of autistic and developmentally impaired adolescents.

A sample of 43 autistic and developmentally impaired adolescents were assessed with the Autism Diagnostic Interview (ADI), DSM-III-R criteria, and the clinician's diagnosis. DSM-III-R criteria for autism have low specificity and agree poorly with the other two definitions. Detailed results of the ADI are provided that confirm the usefulness and discriminant validity of this semi-structured diagnostic interview in a sample of very retarded autistic subjects.