What is the success rate of ABA therapy?
There is no single success rate for ABA therapy. Studies report average gains across groups of children, not a pass or fail rate, so any provider quoting one number is not quoting the research.
Here is what the studies actually measure, why published numbers disagree, and what success should mean for your child.
Controlled studies measure average change on communication and daily living scores. None of them report a percentage of children who succeeded.
Why is there no single success rate for ABA therapy?
Because researchers do not measure ABA that way. Studies track how much a group of children changed on specific scores, then compare that to children who did not receive the therapy. There is no finish line a child either crosses or misses.
That matters when you compare providers. A clinic advertising a specific success percentage is not citing this research, because this research does not produce one.
| Study | What it pooled | What it reported |
|---|---|---|
| Eldevik et al., 2009 | 9 controlled studies | IQ gains at effect size 1.10, daily living gains at 0.66. |
| Eckes et al., 2023 | 11 controlled studies, 632 children | Intellectual functioning 0.51, adaptive behavior 0.37, versus usual care. |
| Rodgers et al., 2021 | 491 children, re-analyzed individually | Gains held up child by child, with no clear advantage for younger starters. |
An effect size is simply how big a difference is. Above 0.8 counts as large and 0.5 is moderate. None of these numbers is a success rate.
What about the famous 47% figure?
That number comes from a 1987 UCLA study by Ivar Lovaas, in which 9 of 19 children reached typical school placement after roughly 40 hours a week of therapy.
Children in that study were not randomly assigned to groups, which is a real methodological problem, and stricter replications since have found smaller results. Treat a provider quoting 47% as a promise the way you would treat any sales claim.
Q: Does that make the evidence weak?
A: No. The modern meta-analyses are stronger than the 1987 study precisely because they pool many trials. The benefit still shows, at more realistic sizes.
What published success numbers leave out
Averages assume children actually receive the therapy that was prescribed. Many do not.
Among 334 children referred for ABA at Kaiser Permanente Southern California, 66% were still receiving it after 12 months and 46% after 24 months. Of those who stopped at 12 months, only 14% stopped because they had met their treatment goals (Choi et al., 2022). Most stopped for reasons like cost, a move, or an insurance change.
Q: Why does that matter to me?
A: A program only helps if your family can sustain it. Coverage and schedule fit are part of whether therapy works, not separate from it.
What should success mean for your child?
Averages do not raise your child. Success is measurable movement on goals your family chose, and you should be able to see it in the data your BCBA collects.
At Budding Futures ABA, Clinical Director Rachel Blackburn, BCBA sets goals from assessments like VB-MAPP and ABLLS-R, and a BCBA supervises about 20% of therapy hours, four times the BACB minimum. Close supervision is what makes a stall visible early enough to change course.
ABA is not a cure and should never be sold as one. The honest goal is small, real, measurable wins that hold up outside the session.
Frequently asked questions from parents
Q: Is there an official ABA success rate?
A: No. The major meta-analyses report average effect sizes on skills like communication and daily living, not a success percentage. A single number presented as the success rate of ABA is not coming from that research.
Q: What do the studies actually report?
A: Eldevik et al. (2009) pooled nine controlled studies and found large average IQ gains (effect size 1.10) and moderate daily living gains (0.66). Eckes et al. (2023) pooled 11 studies covering 632 children and found medium gains in intellectual functioning (0.51) and adaptive behavior (0.37).
Q: Why do some families say ABA changed everything and others say it failed?
A: Quality varies enormously between providers, and so does fit. The same method delivered by a different team, in a different setting, can produce very different results for a similar child.
Q: Do most children finish the program that was prescribed?
A: No. Among 334 children referred for ABA at Kaiser Permanente Southern California, only 28% of those who stayed two years received at least 80% of the hours originally prescribed (Choi et al., 2022).
More on effective ABA therapy
Is ABA Therapy Effective?
What controlled studies show, in plain English.
How Do I Know If ABA Is Working?
Separate real trends from good days.
Effective ABA Therapy Near Denver
How Budding Futures delivers BCBA-supervised ABA at home across Colorado.
Sources
Eldevik et al., 2009
Meta-analysis of Early Intensive Behavioral Intervention, Journal of Clinical Child & Adolescent Psychology.
Eckes et al., 2023
Comprehensive ABA-based interventions meta-analysis, BMC Psychiatry.
Rodgers et al., 2021
Intensive behavioural interventions based on ABA: individual participant data meta-analysis, Autism.
Choi et al., 2022
Patient Outcomes After Applied Behavior Analysis for Autism Spectrum Disorder, Journal of Developmental & Behavioral Pediatrics.
Want to know what progress would look like for your child?
Tell us your child’s goals and we’ll explain what a BCBA would measure, how soon you would see it, and how Medicaid or your insurance covers it.