This page of our free RBT Exam Study Guide covers measurement. This is based on Section A of the RBT Task List, which includes the following tasks related to the measurement of behaviors:
- Prepare for data collection
- Implement continuous measurement procedures (e.g., frequency, duration)
- Implement discontinuous measurement procedures (e.g., partial & whole interval, momentary time sampling)
- Implement permanent-product recording procedures
- Enter data and update graphs
- Describe behavior and environment in observable and measurable terms
Significance of measurement in ABA: Measuring behaviors is an essential component of ABA. Without data, it is impossible to objectively determine how much progress a learner is making.
RBTs will record data on their client’s behaviors and skills targeted each time they work with them. Behavior analysts and case supervisors review and analyze the data to determine the learner’s progress and decide whether to continue doing things the same or make changes. This is called data-based decision-making.
RBT Task A-1: Prepare for Data Collection
You can expect to record data each session. At the start of your session, review the goals you’ll be recording data on and identify what materials you’ll need.
Some of the materials you might need for data collection include:
- Paper data sheets and a pen (if your company uses paper data collection)
- Tablet or other device with your electronic data system open and logged in (if your company uses digital data collection)
- Timer to track the duration, interresponse time, or response latency of target behaviors
- Clicker to count the number of times a target behavior occurs
Tip: Have all materials easily accessible. When working with some clients, you may switch between locations frequently (i.e., from the living room to the kitchen, then down to the basem*nt), so be sure your materials can be grabbed quickly and brought along.
RBT Task A-2: Implement continuous measurement procedures (e.g., frequency, duration)
RBTs use many different types of measurement when tracking behaviors and skills. Your BCBA will determine the type of measurement to use based on the client, the target behavior, and other variables.
When recording data using continuous measurement, you should record every occurrence of the target behavior. These measures are used when it’s feasible to record all occurrences. If there are barriers to recording all occurrences, BCBAs usually opt for discontinuous measurement instead (See A-3).
There are five main types of continuous measurement.
- Count: The number of times a behavior occurs.
Count examples: Patrick punched his brother 3 times; Sally independently manded for a cookie 1 time.
- Frequency/rate: The number of times a behavior occurs over a particular time period. To differentiate between count and rate, look for a measure of time. If a measure of time is included (i.e., per hour, per day, per week, etc.), then it’s a rate measurement.
Frequency/rate examples: Dahlia bit her hand 6 times per hour; Sammie cooks dinner 5x per week.
- Response latency: The duration of time that passes from the onset of an SD (the SD is often the instruction/demand) to the start of the behavior.
Response latency examples: A mom tells her daughter, “Come sit down. It’s time for dinner.” The daughter comes to the table 3 minutes later. The response latency would be 3 minutes.
You tell your client, “It’s time to put the toys away.” They run around the room laughing for 30 seconds before starting to clean up their toys. The response latency would be 30 seconds.
- Interresponse time (IRT): The duration of time that passes from the end of a response to the beginning of the next response.
Interresponse time (IRT) examples: Maya raises her hand in class at 9:00 AM, then again at 9:05 AM. The IRT between her raising her hand would be 5 minutes.
Your client engages in self-stimulatory spinning from 4:32 until 4:34. The next occurrence starts at 4:40. The IRT of spinning would be 6 minutes, as the last occurrence ended at 4:34, and the next occurrence started at 4:40.
- Duration: A total amount of time from the beginning of a behavior to the end of it.
Duration examples: Benji screams for 3 minutes; Aniyah reads a book for 22 minutes.
RBT Task A-3: Implement discontinuous measurement procedures (e.g., partial & whole interval, momentary time sampling)
Discontinuous measurement procedures are a way of measuring behavior by recording some occurrences of the behaviors but not all. These are often used when there are barriers to recording all occurrences of the behavior. For example, in a classroom, a teacher may not be able to record every time a behavior occurs due to attending to multiple students at a time.
There are three main discontinuous measurement procedures.
- Whole interval recording:
Break an observation period into equal intervals (e.g., 30 seconds, 5 minutes, 20 minutes).Next, record data on whether the target behavior occurs throughout the whole duration of the interval. If the behavior did occur for the entire interval, mark that interval as a “yes,” “+,” or “✔.” If the behavior did not occur for the entire interval, mark the interval as a “no,” “–,” or “X.”
Important note: If the behavior occurred for only part of the interval, do not record it as a “yes.”
Whole interval recording example: Lilah is taking whole interval data for her client’s repetitive spitting. The session is broken up into 2-minute intervals. Every 2 minutes, she records whether her client spits for the full 2-minute interval. If her client did not spit at all OR spit for some of the interval, but not the whole time, Lilah marks “–” for that interval. When her client spits for a full 2-minute interval, Lilah marks “+” for that interval.
- Partial interval recording:
Break an observation period into equal intervals, similar to whole interval recording.Next, record data on whether the target behavior occurs AT ALL during the interval. If the behavior occurs during the interval, mark it as a “yes,” “+,” or “✔.” If the behavior did not occur at all during the interval, mark it as a “no,” “–,” or “X.”
Important note: It doesn’t matter if the client engaged in the behavior once, twice, or for the whole time. If the behavior is observed at all during the interval, mark it as occurring.
Partial interval recording example: You are instructed to take partial interval data for your client’s head-banging self-injurious behavior (SIB) in 7-minute intervals. Every 7 minutes, you record a “✔” if your client bangs his head at all during the previous 7 minutes, and you record an “X” if your client does not bang his head at all during the previous 7 minutes.
- Momentary Time Sampling:
Break an observation period into equal intervals.At the end of each interval, observe whether the target behavior is currently occurring.
If the behavior is occurring at the end of the interval, mark the interval as a “yes,” “+,” or “✔.” If the behavior is not occurring at the end of the interval, mark the interval as a “no,” “–,” or “X.”
Momentary time sampling example: A 6th-grade teacher has two students who tend to lose focus during independent work time. The teacher breaks a 45-minute independent work period into nine 5-minute intervals. She grades assignments while the students are working. At the end of each 5-minute interval, she briefly looks up to see if those students are attending to their work. If they are attending to their work at that time, she marks a “+”. If they are not attending to their work at that time, she marks a “–”.
RBT Task A-4: Implement permanent-product recording procedures
Permanent product recording involves indirectly measuring behavior based on a permanent product of the behavior. A permanent product is a concrete outcome of the behavior.
Permanent product recording example: A teacher measures his student’s homework completion based on the final product: whether or not the student turned in a completed homework assignment.
RBT Task A-5: Enter data and update graphs
The data from behaviors and skills targeted are charted on graphs. RBTs assist by updating the graphs with their session data. BCBAs analyze the graphs to make treatment decisions. Graphs can be handwritten, created in Excel/Google Sheets, or auto-generated in a digital data system.
The line graph is the most frequently used type of graph in ABA. Each data point is connected by a line.
The X-axis is horizontal on a graph. On this axis, you record the date or session number.
The Y-axis is vertical on a graph. On this axis, you record the measure of the behavior (e.g., the duration, percentage, rate, etc.). See the example of a line graph below.
RBT Task A-6: Describe behavior and environment in observable and measurable terms
In ABA, we talk about behaviors in terms that are both observable and measurable. When referencing a learner’s behavior, focus solely on actions that can be objectively observed and measured. Don’t add language based on your thoughts or assumptions. For example, you might say, “Client ran from RBT when instructed to sit down,” NOT “Client was really hyper today and didn’t want to listen.” Running is an observable behavior. You can measure running in terms of duration (i.e., they ran for 2 minutes). However, you cannot objectively measure being “hyper.” You also can’t assume that the client didn’t want to listen.
Behavior analysts use something called the “Dead Man’s Test” to determine if something is a behavior or not. If a dead man (or a stuffed animal/inanimate object) can do something, then it’s not a behavior. For example, a dead man can be non-compliant. If you were to say, “Come here,” they would not listen. Therefore, non-compliance is not a behavior.
RBT Measurement Review Quiz
Next Study Guide Unit
Unit B: Assessment
