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Study: Autism Therapy Produces Greatest Gains When Started Before Age 2

October 07, 2014

In a study with toddlers, intensive behavioral intervention helped all ages, but those who started before age 2 were most likely to make dramatic gains

(Oct 7, 2014) A new study provides further evidence that earlier intervention for autism increases the likelihood that a child will make significant gains in social and communication skills.

The report appears in the journal Research in Developmental Disabilities.

In the study, researchers at The New England Center for Children enrolled 83 toddlers diagnosed with autism in the school’s Early Intensive Behavioral Intervention program. The program, based on the principles of Applied Behavior Analysis (ABA), provided 20 to 30 hours of one-on-one therapy each week. The children were between 1 and 3 years old at the time they began therapy.

After one year of intervention, testing showed gains in social and communication skills across all age groups. These skills included sharing attention with another person, interactive play, imitation and language. To gauge the extent of these gains, the researchers compared each child’s skill levels at the end of the year to both the child’s skill level on entering the program and the skills of an age-matched comparison group of 58 typically developing children.

While all age groups showed improvements, a much larger percentage of the youngest participants made significant gains in skills during the year of therapy.

* Among the toddlers who entered the therapy program before their second birthday, 90 percent (11 out of 12 children) made significant gains.

* This was true of 70 percent (26 of 36) of those who began therapy between 24 and 29 months of age.

* By contrast, only 30 percent of the children who entered therapy after 30 months of age (11 out of 35) made significant gains across the year.

“These findings add to past research showing that early intervention improves outcomes of children with autism,” comments Lucia Murillo, Autism Speaks assistant director of education research. “This is why early diagnosis is so critical.” However, with only 12 children in the youngest age group, Dr. Murillo and the study authors agree that larger studies are needed to determine whether there is, in fact, such a large difference in benefit depending on whether therapy begins before the second birthday.

The study findings underscore the importance of the American Academy of Pediatrics recommendation for autism screening at 18 months. They likewise support efforts to expand the availability of high-quality early intervention for all children affected by autism.

To screen your toddler with the interactive and automated Modified Checklist for Autism in Toddlers (M-CHAT), visit “Screen Your Child” on the Autism Speaks website.

Also needed is further research to determine how best to identify which children will respond best to behavioral therapy and to develop more effective treatments for those who respond poorly.

The New England Center for Children provides evidence-based educational services to children with autism. To learn more about The New England Center for Children, visit