Assessment & Research

Predicting spoken language level in children with autism spectrum disorders.

Stone et al. (2001) · Autism : the international journal of research and practice 2001
★ The Verdict

For toddlers with ASD, strong motor imitation and plenty of speech therapy hours predict talking at four, but dosage and AAC tools may override that risk.

✓ Read this if BCBAs who assess or write plans for toddlers with ASD.
✗ Skip if Clinicians serving only school-age or non-autistic learners.

01Research in Context

01

What this study did

The team watched 25 two-year-olds with autism for two years.

They recorded each child’s motor imitation, play, joint attention, and weekly therapy hours.

At age four they tested spoken language to see which early signs mattered most.

02

What they found

Only two things forecast age-four talking: how well the child copied actions and how many speech-therapy hours he got.

IQ, play level, and autism severity added no extra power.

03

How this fits with other research

Thurm et al. (2007) later repeated the work with the kids and got the same result—imitation and joint attention still rule.

Slater et al. (2020) then showed the next step: kids with mild symptoms need 25 ABA hours to grow language, but severe kids do not gain more at that dose.

Rose et al. (2020) flipped the lens inside an AAC-rich class and found that how quickly a toddler looks at, then uses, new AAC symbols now beats imitation for predicting gains.

The papers do not clash—they simply move from “what child traits matter” to “how setting and tools change what matters.”

04

Why it matters

You can spot risk at intake. Run a quick imitation probe and tally speech-therapy hours. If both are low, keep hours high and add imitation drills first. Re-check after six months and adjust dose or shift to AAC if the child is still not talking.

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Count the child’s weekly speech hours and give five rapid motor-imitation trials; if either number is low, bump speech hours or add 10 daily imitation trials.

02At a glance

Intervention
not applicable
Design
pre post no control
Sample size
35
Population
autism spectrum disorder
Finding
not reported

03Original abstract

Thirty-five children who received an autism spectrum diagnosis at the age of 2 years (24 with autism, 11 with PDD-NOS) were re-evaluated 2 years later to examine factors related to the development of spoken language. Child variables (play level, motor imitation ability and joint attention) and environmental variables (socioeconomic status and hours of speech/language therapy between ages 2 and 3) were used to predict an aggregate measure of language outcome at age 4. After controlling for age 2 language skills, the only significant predictors were motor imitation and number of hours of speech/language therapy. Implications of these results for understanding the early developmental course of autism spectrum disorders and the effects of intervention are discussed.

Autism : the international journal of research and practice, 2001 · doi:10.1177/1362361301005004002