Autism & Developmental

Differences in adaptive functioning among people with autism or mental retardation.

Jacobson et al. (1990) · Journal of autism and developmental disorders 1990
★ The Verdict

Autistic children may look more capable than IQ-matched peers, but their daily-living skills fall behind by adulthood—so start adaptive training early and never stop.

✓ Read this if BCBAs working with autistic learners older than five and any team planning transition services.
✗ Skip if Clinicians serving only infants or adults with profound ID and no autism.

01Research in Context

01

What this study did

The team compared daily-living skills in two groups: autistic kids and kids with mental retardation matched for age and IQ.

They tracked the same people from childhood (ages 5-12) into adulthood.

No treatment was given; they just watched how skills changed over time.

02

What they found

In childhood, autistic kids scored higher on daily-living tests than their IQ-matched peers with MR.

By adulthood the picture flipped: the autistic group now showed weaker adaptive skills.

The gap reversal means the MR group caught up while the autism group slowed down.

03

How this fits with other research

Deserno et al. (2017) followed bright autistic adults without ID and found the same adult gap—daily-living skills lagged far behind IQ.

Pathak et al. (2019) looked at thousands of autistic children and saw the childhood gap too; higher-IQ kids often had lower adaptive scores than expected.

Austin et al. (2015) watched preschoolers with autism for three years and found tiny adaptive gains even when IQ jumped 10-15 points—an early warning that skills don’t keep up with smarts.

04

Why it matters

If you work with autistic clients, don’t trust a high IQ score to mean high independence. Start adaptive-skills programs early and keep them running through adolescence. Track dressing, cooking, money, and social navigation every year. When you see a widening gap, add direct instruction and parent coaching instead of waiting for skills to “catch up.” They won’t without help.

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→ Action — try this Monday

Add one adaptive goal—like making a sandwich or paying for an item—to the next session plan, even if the learner’s IQ looks strong.

02At a glance

Intervention
not applicable
Design
other
Sample size
25490
Population
autism spectrum disorder, intellectual disability
Finding
mixed

03Original abstract

This report describes differences in motoric and instrumental activity of daily living skills (MADLs and IADLs) between 1,442 people with autism and 24,048 people with mental retardation, using data from an adaptive behavior measure. Comparisons were made using groups defined by age (5-12, 13-21, and 21-35 years) and intellectual level. Diagnoses of record were confirmed through group analyses of rates of problem behaviors consistent with autism and comparison to an independent data base. Findings suggest that at ages 5-12 the skills of children with autism are more developed than those of children with mental retardation matched by age and intellectual level. However, in the older groups these differences diminish, and with increasing age (21-35 years) more developed instrumental skills are observed for people with mental retardation.

Journal of autism and developmental disorders, 1990 · doi:10.1007/BF02284719