Behavior Momentum in ABA: 5 Steps to Build a High-P Sequence

A learner runs through five easy instructions without a hitch, then stalls at the step that matters most. Board Certified Behavior Analysts (BCBAs) and Registered Behavior Technicians (RBTs) run into this challenge often, and a high-probability (high-p) request sequence is a tool designed to address it.

Behavior momentum research shows that the outcome of a high-p sequence comes down to a few decisions: the ratio of easy to hard requests, the pace between them, and how quickly the easy ones are reinforced. Here's how it all works.

What is behavior momentum in ABA?

Behavior momentum in Applied Behavior Analysis (ABA) is the tendency for compliance to carry over from one request to the next. Once a learner builds up a pattern of following easy instructions, that same cooperation tends to flow into a harder instruction.

The idea comes from behavior momentum theory, which compares reinforced behavior to a moving object. The more reinforcement a response has picked up in a given setting, the harder it is to knock that response off course. A high-p sequence is a technique for building this momentum.

You deliver a handful of easy, well-known instructions or requests right before a harder one. The learner's momentum from those easy wins carries into the tougher task.

You’ll use instructions the learner already knows, so there are no new materials, extra session time, or added cost to consider.

How does the high-p request sequence work?

The high-p sequence works by stacking two to five easy requests or instructions before a difficult one.

The easy instructions, called high-p requests, have a strong history of compliance. The final instruction, a low-probability (low-p) request, is one the learner usually resists or avoids.

A typical sequence might look like this during a transition:

• "Touch your nose." (high-p)
• "Give me five." (high-p)
• "Clap your hands." (high-p)
• "Put your shoes on." (low-p)

Each high-p request gets quick praise or a small reinforcer: anything the learner finds motivating enough to keep up compliance. That fast pace of reinforcement is what brings the momentum into the harder task.

Getting the ratio right

The ratio of high-p to low-p requests affects how well the sequence works.

A 3:1 ratio is most often used in behavior momentum research, but at least one study has found a 5:1 ratio to result in stronger compliance. It may be worth testing a higher ratio if your learner plateaus at 3:1.

Does behavior momentum actually work?

Yes, high-p sequences have shown strong, consistent results for learners with autism, and the technique is considered a promising evidence-based practice.

The sequence is likely to be effective beyond the session, too. In one study, parents and medical staff with no formal ABA training used a high-p sequence to improve compliance during medical exams and saw clear gains.

Researchers have also found a high-p sequence to work for handling several low-p requests in a row, though extra reinforcement may be necessary.

How do you build a high-p sequence?

You build a high-p sequence by identifying the target low-p task, choosing two to five known high-p tasks, and delivering them in quick succession before the low-p request.

These five steps make the difference between a sequence that works and one that fizzles out:

1. Pick genuinely easy tasks

The high-p tasks you choose need a near-perfect compliance history. A task that only feels easier compared to the target won't build real momentum.

2. Move quickly between requests

Deliver each high-p instruction as soon as you can after the last. Long pauses give the momentum time to fade before the low-p request even arrives.

3. Reinforce every high-p response

Praise or a small reward after each easy request keeps the level of reinforcement high enough to carry into the harder task.

4. Watch for high-p tasks losing their effect

If the learner starts resisting high-p tasks, too, swap in new ones. This keeps the sequence from losing its effect over time.

5. Track what's happening

Your sequence is only effective if the ratio, timing, and task selection are right, so accurate session data is essential for knowing whether your sequence works.

Without this insight, a stalled sequence is hard to fix, since there's no way to tell if the problem is the ratio, the timing, or the tasks themselves.

Track behavior momentum in ABA with Passage Health

A high-p sequence moves fast. Five or six requests can happen in a couple of minutes, which leaves very little time to take notes.

Passage Health is a mobile app and clinical platform that’s built to keep up with that pace while giving you and your payors a detailed picture of progress.

Here's how it fits into your workflows:

• Log compliance as it happens: RBTs can record compliance data straight into our mobile app during sessions. Everything syncs automatically, so there’s no lag between data entry and review.
• See the trend, not the raw numbers: Automated graphing turns session-by-session compliance into a customizable treatment report, so it’s easy to tell if the sequence needs adjusting.
• Keep plans running smoothly: Enhanced scheduling features let you filter calendars by billing code, certification status, and learner team, so reassignments are easy, and progress isn’t disrupted.
• Connect session data to billing: Claims generate directly from session data, with real-time visibility into the billing pipeline to help minimize admin.
• Catch authorization issues early: Our system tracks approved hours per learner and flags payor compliance issues before a claim goes out, so billing teams catch problems before they turn into denials.
• Spot patterns across your caseload: Practice-wide reporting rolls individual session data into utilization insights, so clinical directors can see how programs are performing across the practice.
• Simplify intake before treatment starts: Our Client Intake tools keep communication and data organized from the first inquiry, so prospective clients never get lost in spreadsheets or email threads.
• Draft notes faster: Our integration with Frontera AI helps turn logged session data into clinical documentation first drafts, so BCBAs can focus on reviewing and editing.
• Get new features every quarter: The platform updates every quarter based on what our practices ask for.

Everything runs through one simple, intuitive platform. This means no separate systems for data collection, scheduling, and billing, and no steep learning curve for an RBT picking up a sequence mid-week. Every new team gets 1:1 onboarding support to get set up smoothly.

Book a demo to see how Passage Health can help your team run behavior momentum sequences without slowing down.

Frequently asked questions

What is a high-probability request sequence?

A high-probability request sequence is a technique that pairs several easy, well-known instructions with one harder instruction right after. Compliance with the easy requests builds enough momentum to carry into the harder one.

How many high-p requests should come before a low-p request?

The most common ratio of high-p to low-p requests is 3:1, though a 5:1 ratio has produced stronger results in at least one comparison. You might start at 3:1 and only move up if a learner's compliance stalls, since a higher ratio means spending more time on requests that were never the target.

Is behavior momentum the same thing as a high-p request sequence?

The main difference between behavior momentum and a high-p request sequence is that one is a theory and the other is the technique built from it. Behavior momentum explains why reinforced behavior resists disruption, and the high-p sequence is a way to keep compliance going.

Can behavior momentum reduce challenging behaviors?

Yes, an effective high-p sequence (a technique that stems from behavior momentum theory) can help reduce challenging behaviors tied to avoiding tasks. It works because the sequence raises compliance before the learner has the chance to escalate. 

References

Ertel, H., Wilder, D. A., Hodges, A., & Hurtado, L. (2019). The effect of various high-probability to low-probability instruction ratios during the use of the high-probability instructional sequence. Behavior Modification, 43(5), 639–655. https://doi.org/10.1177/0145445518782396

Nevin, J. A., & Shahan, T. A. (2011). Behavioral momentum theory: Equations and applications. Journal of Applied Behavior Analysis, 44(4), 877–895. https://doi.org/10.1901/jaba.2011.44-877

Riviere, V., Becquet, M., Peltret, E., Facon, B., & Darcheville, J.-C. (2011). Increasing compliance with medical examination requests directed to children with autism: Effects of a high-probability request procedure. Journal of Applied Behavior Analysis, 44(1), 193–197. https://doi.org/10.1901/jaba.2011.44-193

Rosales, M. K., Wilder, D. A., Montalvo, M., & Fagan, B. (2021). Evaluation of the high-probability instructional sequence to increase compliance with multiple low-probability instructions among children with autism. Journal of Applied Behavior Analysis, 54(2), 760–769. https://doi.org/10.1002/jaba.787

Sayar, K., Gulboy, E., Yucesoy-Ozkan, S., & Baran, M. S. (2024). High-probability request sequence to increase compliance of children with autism spectrum disorder: A meta-analysis. Behavioral Disorders, 50(1), 17–33. https://doi.org/10.1177/01987429231224044