Predictors of treatment outcome in young children with autism: a retrospective study.
Early thinking scores, not clock hours, shape long-term success for toddlers with autism.
01Research in Context
What this study did
The team looked back at charts for toddlers with autism. They wanted to know why some kids did much better after three years of therapy.
They split the children into high- and low-outcome groups. Then they checked if hours of therapy made the difference.
What they found
Hours of therapy were the same for both groups. The big hint was early IQ. Kids who started with higher thinking scores tended to land in the high-outcome group.
Treatment intensity did not predict who would thrive.
How this fits with other research
Levin et al. (2014) seems to disagree. Their study shows kids who get 30-plus hours of ABA score far higher on IQ tests than kids in mixed programs. The gap is real, but the designs differ. Gabriels et al. (2001) counted hours within one generic program; S et al. compared two whole models.
Heavey et al. (2000) tells the same story one year earlier. Younger age and IQ above 70 raised the odds of later regular-class placement.
Hastings et al. (2001), published the same year, also found no IQ gain after parent-managed intensive ABA. The replication across two 2001 papers strengthens the warning: intensity alone is not enough.
Rodgers et al. (2021) pools 491 kids and shows small-to-medium IQ gains for intensive ABA. Their meta-analysis now sits on top of the older case series, giving us firmer numbers.
Why it matters
Check early developmental IQ during intake. If it is low, plan for more teaching reps and visual supports, not just more hours. Share this data with families so they know progress may be slower yet still possible.
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02At a glance
03Original abstract
This study examined predictors of developmental outcomes in 17 children diagnosed with autism or PDD-NOS, who received generic treatment over a mean period of 37 months. Pre-treatment evaluations occurred at a mean age of 31 months with follow-up evaluations at a mean age of 69 months. Significantly different developmental trajectories were observed among the participants at follow-up, separating the participants into two distinct groups (high and low outcome). However, groups did not differ significantly in treatment intensity or other outcome prediction measures. Pre-treatment developmental intelligence levels between the two groups approached significance. The results raise questions regarding the effect of treatment intensity and type, family stress factors, and intelligence ability in very early childhood on, outcome.
Autism : the international journal of research and practice, 2001 · doi:10.1177/1362361301005004006