New Study Finds 91% Drop in Severe Behavior With Intensive ABA Treatment

For families whose autistic child struggles with severe behaviors like aggression, self-injury, or property destruction, finding treatment that actually works can feel like an impossible search. A new study out of Atlanta's Marcus Autism Center, published in the Journal of Developmental & Behavioral Pediatrics, offers some of the strongest evidence yet that intensive behavioral treatment can produce real, measurable change, even for children facing the most severe presentations of these behaviors.

What the Study Found

Researchers Meara McMahon, Mindy Scheithauer, Nathan Call, William Sharp, and Colin Muething, working out of Marcus Autism Center and Emory University School of Medicine, reviewed the records of 40 children and adolescents ages 6 to 19 who were treated in the center's intensive outpatient program between January 2020 and December 2023. Every participant had an autism diagnosis, and 80% also had a co-occurring intellectual disability.

These were not children with mild behavioral challenges. Before treatment:

• 87.5% of participants displayed aggression toward others
• 82.5% displayed disruptive behavior
• 67.5% engaged in self-injurious behavior

Many of these children were considered at immediate risk of harming themselves or others, the kind of behavior that can make it difficult to find any provider willing to take them on, let alone a school or community program.

The treatment itself was intensive by design: five hours a day, five days a week, for approximately five months, totaling roughly 500 clinic hours. By the end of treatment, researchers found a 91% reduction in severe externalizing behaviors, and 82.5% of participants achieved their primary treatment goal.

Why This Study Matters for Parents

Severe behavior is one of the most under-discussed and under-resourced areas in autism care. Parents of children with aggression or self-injury often describe being turned away from ABA therapy providers who don't have the training or staffing to handle high-intensity cases safely. Many end up cycling through emergency rooms, psychiatric hospitalizations, or school suspensions because no outpatient program felt equipped to take them. This study is a reminder that specialized, sufficiently intensive behavioral treatment exists and can produce meaningful change, even for children who have been told they are "too severe" for standard outpatient care. It also reinforces something behavior analysts have long argued: that dosage and intensity matter, particularly for the most complex presentations, and that a few hours a week of therapy is unlikely to move the needle on behaviors this entrenched.

Important Caveats to Understand

Reputable research on ABA therapy always comes with limitations, and this study is no exception. The authors themselves describe their findings as "provisional evidence," not a definitive conclusion, and are transparent about several important caveats:

• Single-site study. All 40 children were treated at one program, Marcus Autism Center's Severe Behavior Program, which is a specialized, highly resourced clinical setting. Results may not generalize to every ABA provider or community-based program.
• Small sample size. Forty patients is a meaningful start, but it is not a large enough sample to draw sweeping conclusions about severe behavior treatment nationwide.
• Retrospective design. Researchers reviewed existing electronic health records rather than running a controlled prospective trial, which means there was no control group for comparison.
• Not a coverage or policy statement. The study does not address insurance coverage, Medicaid authorization, or rate disputes. It is a clinical outcomes study, not a policy document, and should not be read as evidence in ongoing debates about ABA therapy hour caps or reimbursement rates.

None of this diminishes the value of the findings. It simply means parents and providers should treat this as an encouraging, well-documented data point, not as a guarantee of what any individual child will experience.

What This Means If Your Child Has Severe Behaviors

If your child is dealing with aggression, self-injury, or other severe behaviors, here is what this research suggests you should look for in a provider:

1. Ask About Their Experience With Severe Behavior Specifically

Not every ABA provider has the training, staffing ratios, or safety protocols to treat severe behavior safely. Ask directly whether the practice has experience with functional behavior assessments (FBAs) for aggression and self-injury, and whether staff are trained in crisis prevention and de-escalation.

2. Understand the Role of Treatment Intensity

This study used a highly intensive model, five hours a day, five days a week. Not every child needs that level of intensity, and not every family can access it, but it's worth asking your provider how they determine the right dosage for your child's specific presentation and how they will adjust it as progress is (or isn't) made.

3. Ask How Progress Is Measured

The Marcus study measured concrete, specific outcomes: reduction in externalizing behaviors and achievement of individualized treatment goals. A good provider should be able to tell you, in specific and measurable terms, what "progress" will look like for your child and how they'll track it over time.

4. Know That Specialized Programs Exist

If your local ABA provider tells you they cannot safely treat your child's behaviors, ask for a referral to a specialized intensive outpatient or day treatment program. Centers like Marcus Autism Center are not the only option, many children's hospitals and university-affiliated autism centers around the country run similar severe behavior programs.

Find an ABA Provider Who Can Help

Whether your child needs a specialized intensive program or a standard outpatient ABA provider, finding the right fit matters. ABA Navigator maintains a directory of ABA therapy providers across the United States, making it easier to compare providers, read reviews, and find help near you. Search our directory to find ABA providers near you and start the conversation about what treatment approach is right for your child.