# Which ABA data collection methods should I use?

> Continuous and discontinuous measurement, when to use each, and how to keep data accurate without slowing sessions down.

URL: https://theautismkit.com/guides/aba-data-collection
By The Autism Kit team · Updated 2026-09-27

**Short answer:** ABA data methods fall into continuous measurement (frequency, rate, duration, latency, trial-by-trial) and discontinuous measurement (partial interval, whole interval, momentary time sampling), plus permanent products. Choose based on the behavior's features and what decision the data needs to support. Accurate, consistent data matters more than collecting everything.

**Key takeaways**
- **Continuous** methods record every instance.
- **Discontinuous** methods **estimate** using intervals.
- Pick the method that fits the **behavior** and the **decision**.
- Check **reliability** and keep data sheets **simple**.

## What are the main data collection methods?

| Method | Best for | Example |
| --- | --- | --- |
| Frequency or rate | Behaviors with a clear start and end | Number of requests per hour |
| Duration | How long a behavior lasts | Minutes of engagement |
| Latency | Time to start after an instruction | Seconds to begin a transition |
| Trial-by-trial | Skill acquisition in structured teaching | Correct and incorrect responses per trial |
| Partial interval | Behaviors you want to decrease; tends to overestimate | Did it happen at all in the interval? |
| Whole interval | Behaviors you want to increase; tends to underestimate | Did it last the whole interval? |
| Momentary time sampling | Ongoing behaviors in groups | Is it happening at the moment the interval ends? |
| Permanent product | Behavior that leaves a result | Worksheets completed |

RBTs learn these methods, plus calculating rate, duration and percentage, in the 2026 40-hour training.[1] Measurement is also a domain on the BCBA exam.[2]

## How do I choose?

Ask: What does the behavior look like? How often does it happen? What decision will these data support? Can staff record it accurately during the session?

## How do I keep data accurate and efficient?

**Try:**
- Clear operational definitions everyone has practiced
- Short, simple data sheets or a well-designed app
- Regular interobserver agreement checks
- Graphing data at least weekly

**Skip:**
- Recording data from memory after the session
- Collecting data nobody reviews
- Changing definitions without retraining

**Data should drive decisions.** Review graphs on a schedule. If a skill isn't moving after a set number of sessions, check procedural integrity, then
  adjust prompts, reinforcement or the goal.

**Caregiver data.** Simple caregiver data, like a checkmark when a routine is completed, can show whether skills are generalizing at home.

## What can I do this week?

- [ ] Check each target has a clear operational definition
- [ ] Match each target to the right measurement method
- [ ] Schedule one interobserver agreement check

Read next: [How do I write measurable ABA goals?](https://theautismkit.com/guides/writing-measurable-aba-goals)

## Common questions

### Which method is most accurate?

Continuous methods capture every instance, so they're usually most accurate. Discontinuous methods estimate and can over- or under-estimate depending on the method.

### Should RBTs take data on every trial?

Not always. Some teams use probe data (first trial or a sample) for skill acquisition to save time. Choose based on the decisions you need to make.

### What's interobserver agreement?

When two observers record the same session independently and compare. It's a common way to check that data are reliable.

## Sources

1. Behavior Analyst Certification Board: RBT 2026 40-hour training requirements and curriculum outline (data collection and graphing). https://www.bacb.com/wp-content/uploads/2023/12/2026-RBT-40-Hour-Training-Curriculum-260313-a.pdf
2. Behavior Analyst Certification Board: BCBA Test Content Outline (6th ed.). https://www.bacb.com/wp-content/uploads/2022/01/BCBA-6th-Edition-Test-Content-Outline-240903-a.pdf

General guidance, not a diagnosis or treatment plan. Talk with your pediatrician or a developmental specialist about your child's care.