DSM-5 symptom expression in toddlers.

Children with autism show more social-communication symptoms and repetitive behaviors than children with typical development or those diagnosed with other developmental disorders; however, non-autistic children often show some behaviors that are associated with autism. We compared the behavioral reports from caregivers of children in these three groups to identify the behaviors that were specific to autism. Children with autism were found to show more of these behaviors, and behaviors that are particularly indicative of autism were identified. These behaviors included social symptoms (approaching others to interact, showing things, looking back while showing, responding to an approaching child, spontaneous imitation) and repetitive behavior symptoms (specific, inflexible play, unusual body movements, strong specific interest, carrying around an unusual object, sensory seeking, and sensory hyper-reactivity).These findings may aid professionals in determining the most appropriate diagnosis for a child between the ages of 12 and 36 months.