Children with autism spectrum disorders (ASD) who receive intensive early intervention at the age of 18 months fare significantly better than those who begin receiving this type of intervention at 27 months of age, according to a new study.

In a randomized, crossover trial, Whitney Guthrie and colleagues explored the outcomes of 82 autistic toddlers participating in an early intervention program called Early Social Interaction (ESI). Half of the toddlers and their caregivers participated in an intensive, individualized version of the program (Individual-ESI) beginning at 18 months, while the other half participated in a much less intensive group intervention (Group-ESI). After nine months, the two groups crossed over to receive the other treatment for nine months.

The researchers report, “Toddlers randomized to Individual-ESI at 18 months showed greater gains during treatment than those starting Individual-ESI at 27 months in receptive/expressive language, social communication, and daily living skills.” They add, “Importantly, these findings were specific to the intensive and individualized parent coaching model compared to group-based treatment, allowing us to rule out the possibility that these timing effects were due to children getting older rather than the treatment itself.”

They conclude, “Our results suggest that even a narrow window of 18 versus 27 months may have an impact on outcomes and underscore the importance of screening and evaluation as young as possible,” adding that research is needed to determine if there are additional benefits to initiating treatment even before 18 months of age.

“The earlier the better: An RCT of treatment timing effects for toddlers on the autism spectrum,” Whitney Guthrie, Amy M. Wetherby, Juliann Woods, Christopher Schatschneider, Renee D. Holland, Lindee Morgan, and Catherine E. Lord, Autism, March 15, 2023 (free online). Address: Whitney Guthrie, Center for Autism Research, Children’s Hospital of Philadelphia, 2716 South Street, Office 5241, Philadelphia, PA 19146, [email protected].

This article originally appeared in Autism Research Review International, Vol. 37, No. 2, 2023

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