Autism & Developmental

A Comparison Controlled Study Examining Outcome for Children With Autism Receiving Intensive Behavioral Intervention (IBI)

Wójcik et al. (2023) · Behavior Modification 2023
★ The Verdict

Center-based IBI for preschoolers with autism can yield large gains in IQ and adaptive behavior versus eclectic special-ed services.

✓ Read this if BCBAs writing IBI treatment plans or defending intensive hours at school-district meetings.
✗ Skip if Clinicians serving only school-age or strictly home-based clients.

01Research in Context

01

What this study did

Wójcik et al. (2023) tracked preschoolers with autism for 14 months. Half got full-day center-based IBI. The other half stayed in eclectic special-ed classes.

The team measured IQ, daily-living skills, and autism severity before and after.

02

What they found

The IBI group made bigger jumps in IQ and self-help skills. Their autism-severity scores also dropped more than the eclectic-group scores.

In short, center IBI beat mixed special-ed services across the board.

03

How this fits with other research

Sánchez-Luquez et al. (2025) ran a near-copy study but had parents deliver the same ABA lessons at home. Kids still gained big, proving the model works in both places.

Bettencourt et al. (2024) asked what inside IBI drives progress. They found every extra hour spent on emotion and behavior lessons predicted better one-year outcomes.

Delprato (2001) warned that rigid drill can stall language. Wójcik’s center program used looser, child-led drills—matching that earlier advice.

04

Why it matters

You now have solid quasi-experimental evidence that full-day center IBI outruns eclectic preschool rooms. Pair this with parent-led data to justify hours, setting, or hybrid plans. Push for emotion/behavior targets inside the day, and keep drills playful, not robotic.

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Add one emotion-regulation program to each learner’s schedule and track the minutes.

02At a glance

Intervention
comprehensive aba program
Design
quasi experimental
Sample size
39
Population
autism spectrum disorder
Finding
positive
Magnitude
large

03Original abstract

This study evaluated the effects of a center-based Intensive Behavioral Intervention (IBI) model for preschool aged children with autism. Outcomes of 25 children receiving IBI was compared to the outcomes of 14 children receiving autism specific, eclectic, special education. Both provisions were described as appropriate treatment options by the professional agency who diagnosed the children, and the decision of where to enroll the child was made by the parents after consultations with the specialists. After 14 months of treatment, children from the IBI group improved significantly on standard scores in intellectual functioning and adaptive behavior and had a significant reduction in autism severity compared to the children in the autism specific, eclectic, special education group. Results suggest that preschool aged children with autism may make large gains in intellectual and adaptive functioning and improvement in autism severity with IBI, and that effects of IBI may be similar to that of EIBI. These findings must be interpreted with caution due to the limitations inherent in the present comparison-controlled design.

Behavior Modification, 2023 · doi:10.1177/01454455231165934