Cognitive ability is associated with different outcome trajectories in autism spectrum disorders.

Variability in clinical expression and in intervention outcome has been described in autism spectrum disorder (ASD). The study examined progress after 1 and 2 years of intervention and compared the impact of baseline cognitive ability on outcome trajectories in 46 children (m = 25.5 months) with ASD. The entire group showed a gradual decrease in autism severity and increase in verbal cognitive scores. Only the low cognitive scores (DQ <70) group significantly improved in fine motor and receptive language scores. Significant gains in adaptive skills were found only for the high cognitive scores (DQ ≥70) group after 2 years of intervention. The entire group progressed with intervention, but only children with higher cognitive levels at baseline transferred their acquired socio-communication skills into daily functioning.