Behavior Observation System for Autism: Analysis of Behaviors among Autistic, Mentally Retarded, and Normal Children

The Behavior Observation Scale is being developed to objectively differentiate autistic, normal, and mentally retarded children of ages 30 to 60 mo. Operational definitions and procedures are described and frequency data from 140 children are reported. Of 59 scale items 26 were significantly different among the subject groups. Further statistical analysis showed that to assess the diagnostic significance of a behavior both the frequency of occurrence per subject and the number of children exhibiting it must be considered concurrently. Methodological problems encountered when attempting to establish objective diagnostic data for the syndrome of autism are discussed.