Medical Necessity in ABA: What It Means and Who Decides

Medical necessity means an ABA service must be clinically needed for a client's diagnosis and condition before a payer will fund it. A payer is the group that pays the bill, such as Medicaid or a private insurance plan. If the payer cannot see that need, it can refuse to pay.

For a BCBA, the phrase shows up everywhere. It shapes how many hours a child gets, how a treatment plan is written, and how each billed session is recorded. The speakers below come at it from different places. One is a health care author, two host a podcast for clinicians, one teaches RBT supervision, and one is a parent.

Where the idea of medical necessity comes from#

Medical necessity did not start in ABA. Dr. Steve Marin made this point on the Rad N Bad panel. He said medicine has worked under this rule for a long time. New behavior analysts often hear the phrase for the first time on the job.

medical necessity has been a fact of life in medicine for 50 years. A newly minted BCBA goes to work and hears this phrase.

From the talk — Dr. Steve Marin

Dr. Marin described a common first reaction. A new BCBA may feel offended that a payer would weigh in. The thought goes something like, "How dare they tell me what to do?" He pushed back on that reaction. In his view, the field ignores 50 years of experience when it never looks outside its own world.

His larger point was about context. If you do not understand the system you work in, he said, then everything feels like a surprise. Medical necessity is part of that system. It is not a personal attack on a clinician's judgment. It is the shared rule every health service lives under, from surgery to speech therapy to ABA.

The money behind medical necessity#

Dr. Marin then turned to money. He asked the panel if they knew how Medicaid works. Medicaid is the public health plan that covers many children who receive ABA.

there is a fixed amount of money allocated- to every child in Medicaid. It's fixed.

From the talk — Dr. Steve Marin

He explained that the amount can differ from child to child. A child with more complex needs may have more set aside. But for each child, the amount is still fixed. This changes how you should think about hours. If one service uses up a large share of that money, other care can suffer.

Dr. Marin named two risks. First, the child may not get other care they need. Second, the health plan itself can be put at risk. He also pushed back on a familiar line of argument. Some providers say a service is medically necessary and that the child will be harmed if the budget is cut. He treated that framing with doubt.

He did not argue for less funding overall. He said he personally thinks society's choice not to fully fund Medicaid is a problem. He has written that health is a social imperative. He cited a return of about four dollars for every dollar spent on community health. His point was narrower. Inside a fixed budget, every hour of one service is an hour of money not spent elsewhere.

Medical necessity should change as the child changes#

On a separate Rad N Bad episode about treatment dosage, Sean Yocum raised a different problem. Dosage here means the number of therapy hours a child gets each week. He described a pattern he sees often. A BCBA recommends a set number of hours. Communication improves, and the hours stay the same. Challenging behavior drops, and the hours still stay the same.

medical necessity should be responsive to changing clinical conditions.

From the talk — Sean Yocum

Yocum said the field calls a number medically necessary and then treats it as permanent. In his view, those two ideas do not fit together. He used a medical comparison. A doctor would not keep a patient on the maximum chemotherapy dose while the patient improves. A doctor would try to lower the dose and see if the same results hold.

He suggested a better question for every case. Do not ask why the child needs a certain number of hours. Ask what would have to happen for the child to no longer need those hours. He pointed to titration and graduation plans as the place this belongs. Titration means lowering the dose step by step. A graduation plan maps out how a client finishes services. This topic overlaps with dosage debates around early intensive behavioral intervention, but the core idea here is simple. A medical necessity call should be tested again as the child grows.

What "no longer needed" looks like#

Yocum's question needs an answer. If hours should step down, what proof shows a child is ready? His co-host Michael Carrero offered a simple version.

Sustainable outcomes. If the, if those skills are able to maintain and you should be working towards demonstrating that they can sustain and maintain across varieties of environments, context, people, you name it.

From the talk — Michael Carrero

Carrero split this into a few parts. First, the skill has to last over time. Clinicians call this maintenance. Second, the skill has to show up in new places, with new people, and in new settings. Clinicians call this generalization. Third, the child should understand the idea behind the skill, not just the tool.

He was clear that rote learning is not enough. A child who memorizes one routine and uses it in one room has not met the bar. He used an image of something sticking to a wall. Does the skill stick only to this one wall, or to all of them? When it sticks everywhere, that is a sign the current level of service may no longer be needed. For medical necessity, this gives the BCBA a clear, data-based reason to reduce hours.

How payers check medical necessity in the paperwork#

Medical necessity is not only a big-picture idea. It is also checked one claim at a time. A claim is a bill sent to the payer for a service. Dr. Jessica Osos covered this in her talk on training RBTs to help with assessments. An RBT is a Registered Behavior Technician, the front-line staff member who works directly with the client.

She walked through what a payer audit looks for on an assessment claim. An audit is a formal review of records to confirm a bill was valid. She listed three elements.

The third element is medical necessity.

From the talk — Dr. Jessica Osos

For that third element, she gave a specific test.

the assessment activity needs to connect to the diagnosis and the specific clinical questions that this reassessment might answer

From the talk — Dr. Jessica Osos

Dr. Osos said this ties back to choosing the right assessment in the first place. The language that shows need should already be in the treatment plan. She also noted that written session notes are required for every billed code. Every unit billed needs a note.

She stressed one more risk. The RBT may be skilled, and the data may be good. But the work must be directed by the supervising clinician. If an auditor cannot find proof of that, the claim may be denied. Her full talk, Delegating with Confidence: Training and Supervising RBTs to Support Assessments, covers how to set up that paper trail.

What medical necessity looks like from the family's side#

Kim Lambert joined a Rad N Bad episode as a parent. Her son received Medicaid-funded ABA. Her story shows how medical necessity rules can feel from the other side of the table.

Medicaid would not pay for services. If we did not use either 15 hours a week or 30 hours a week, those were the only two options.

From the talk — Kim Lambert

Lambert said the choice was tied to school. If her son stayed out of public school, he could keep 30 hours a week. If he went to public school, the family would only get 15 hours. She said it was presented as if 15 hours plus school was a bad choice.

She did not know any better at the time, she said. So she homeschooled her son and kept him in ABA for 30 hours a week. When asked who the process was built for, her answer was direct. She said it was built for the people who signed the checks. To her, it felt like the family was complying just to keep Medicaid funding.

Her account also touched on who had a voice. She described RBTs told what to run and BCBAs who did not spend enough real time with her son. Her son himself, she said, had no voice in the process.

Where experts disagree on who medical necessity serves#

The speakers agree that medical necessity matters. They pull apart on whether payer rules mainly protect the child or mainly protect the budget.

Dr. Marin's view leans toward the payer's logic. He sees medical necessity as a long-standing rule of medicine that BCBAs should learn and respect. He argues that fixed Medicaid budgets make limits on any single service reasonable. A BCBA who insists only they can decide need is, in his view, ignoring decades of experience.

Kim Lambert's account points the other way. In her case, funding rules did not trim hours to protect other care. Instead, the hour options seemed to steer the family away from public school and toward more ABA. She felt the process served the people paying, not her son. Her story suggests payer rules can shape clinical choices in ways a family never agreed to.

Sean Yocum sits on a third line. His concern is less about payers and more about providers. He faults the habit of calling a number medically necessary and then never testing it again. That critique lands on clinicians as much as on funders. All three views can be true at once, but they put the main problem in different places.

What the research says#

Published work in behavior analysis shows the same tension. Papatola and Lustig wrote as peer reviewers for a managed care company (Papatola & Lustig, 2016). A peer review is a scheduled call where a clinician explains the need for treatment to the payer. They described the medical necessity elements payers ask about. They also gave strategies to help providers get services approved.

A later summary lists their core elements. These include a DSM-5 diagnosis supported by symptoms, symptoms that impair daily functioning, and family involvement (Toby et al., 2024). That same paper notes BCBAs have little standard guidance for picking a medically necessary dose. The authors built a tool called the POP-C to guide newer clinicians on hours and setting.

Not everyone agreed with the peer reviewers' framing. One response pointed out that the authors worked for a large insurer (Kornack et al., 2017). It offered guidance on the laws that support access to treatment. It also explained ways to challenge payer decisions that do not match the standard of care.

A parent also wrote in. She disputed the idea that the BCBA's role is to hand treatment off to parents (Beier, 2018). She noted that the insurer had made that hand-off a medical necessity criterion. In her view, parents cannot simply take over a BCBA's training.

FAQ#

What does medical necessity mean in ABA therapy? It means a service must be clinically needed for a client's diagnosis and condition. A payer uses this standard to decide whether to fund the service. Each assessment or treatment activity should connect to the diagnosis and a clear clinical question.

Can ABA hours be reduced once they are approved as medically necessary? Yes, and some experts say they should be. Sean Yocum argues medical necessity should respond to changing clinical conditions. Hours can step down as skills maintain and generalize across settings and people.

What documents prove medical necessity for an ABA claim? The treatment plan should carry the language that shows need. A written session note is required for every billed unit. Records should also show the supervising clinician directed the work, or an auditor may deny the claim.