Duration
Duration is how long a behavior lasts, measured from the moment it starts (onset) to the moment it ends (offset).
Duration measures the temporal extent of behavior. To record it, the RBT starts a timer when the behavior begins and stops it when the behavior ends, using the onset and offset written in the operational definition. Two summaries are common: total duration, which adds up the time across all episodes in a session, and duration per occurrence, which keeps each episode's length so that the mean duration can be calculated.
Duration fits behaviors where how long matters more than how often: tantrums, crying, time spent on task, time spent engaged with peers, time spent completing a hygiene routine, or time out of seat. A goal might be to increase minutes of independent play or to decrease the length of each tantrum. Duration can also be reported as a percentage of the session, for example 18 minutes of on-task behavior in a 30-minute session is 60%.
Duration requires the observer to watch continuously and to agree on exactly when the behavior starts and stops, so clear onset and offset criteria are essential. It is a poor fit for very brief behaviors such as a single hit or a blink, where frequency is more useful. It also hides how many episodes occurred unless the number of episodes is recorded as well.
Example and non-example
| Example | An RBT starts a stopwatch when a child drops to the floor screaming and stops it when the child has been quiet for 5 seconds, as the definition says, then records 3 minutes 40 seconds. |
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| Non-example | Timing how long it takes a client to start brushing their teeth after the instruction "Brush your teeth" is latency, not duration. |
Don't confuse it with
| Latency | Latency is the time from a cue to the start of the response; duration is the time from the start to the end of the response. |
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| Mean duration | Duration is the time of one episode or the total across episodes; mean duration is the total divided by the number of episodes. |
Test yourself
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Question 1Which of these is a continuous measurement procedure?
Show answer
C: Duration recording. Continuous measurement captures every occurrence of the behavior during the observation period. Duration recording times each occurrence from start to end, so nothing is missed; the interval and time-sampling procedures record only a sample.
- A: Partial interval recording only notes whether the behavior happened at some point in each interval, so it samples the behavior.
- B: Momentary time sampling checks the behavior only at the moment each interval ends.
- D: Whole interval recording only notes whether the behavior lasted through each entire interval.
Task A.1 · 40-hour curriculum section C
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Question 2A plan asks an RBT to record how long each of a teen's pacing episodes lasts, from the first step to the last. Which dimension of behavior is being measured?
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C: Duration. Duration is how long a behavior lasts from its onset to its offset. Timing each pacing episode from the first step to the last is duration recording.
- A: Latency is the time from a cue to the start of a response, not how long the response lasts.
- B: Frequency tells how many episodes happened, not how long each one lasted.
- D: Interresponse time is the gap between two episodes, not the length of an episode.
Task A.1 · 40-hour curriculum section C
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Question 3An RBT is asked to record how long each of a young child's tantrums lasts. Which item does the RBT need in order to do this?
Show answer
A: A stopwatch or timer. Duration recording means timing each occurrence from onset to offset, so the RBT needs a stopwatch, timer or a data app with a timing function.
- B: A tally counter counts occurrences but cannot show how long each tantrum lasts.
- C: A task analysis checklist is used to score the steps of a skill chain, not to time a behavior.
- D: A list of preferred items helps with reinforcement, not with measuring how long a behavior lasts.
Task A.1 · 40-hour curriculum section C
Answer every question to see your score.
On the RBT exam
This term belongs to task A.1 Continuous measurement in content area A, Data Collection and Graphing, which is 13 of the 75 scored questions.