Spoken language outcomes in limited language preschoolers with autism and global developmental delay: RCT of early intervention approaches

Preschool autistic children with significant global developmental delays and very limited language skills are at high risk for remaining minimally verbal at entry into primary school. This study compared two early intervention models for improving social communication and spoken language outcomes in 164 children who received intervention in their community preschool program for 6 months, with a six-month follow-up. The primary outcome measure was a standardized language assessment, and secondary measures focused on social communication. Results indicated children on average made 6 months gain in language development in the active 6 months of intervention with no difference between intervention models. Children who initiated joint attention more frequently, or who had higher receptive language at baseline made more progress if assigned to receive JASPER, a naturalistic developmental behavioral intervention. Children who received Discrete Trial Training made greater spoken language progress from exit to follow-up. These findings suggest that progress can be made in autistic children who have very little spoken language and who receive targeted early interventions. Individual trajectories vary and depend in part on initial abilities in social communication and receptive language. Future research might consider methods to systematically personalize approaches to fit child characteristics and family preference.