Co-existence of disorders--including attention-deficit/hyperactivity disorder, oppositional defiant disorder, tic disorder, developmental coordination disorder, and autism spectrum disorder--and sharing of symptoms across disorders (sometimes referred to as comorbidity) is the rule rather than the exception in child psychiatry and developmental…

The variability in outcomes observed in home-based early intensive behavioral intervention for children with autism is likely in part to be the result of the quality of therapist performance. Therapist behavior in this context, however, is poorly understood. To achieve such an understanding, it will be necessary to specify how factors such as…