Time delay
A prompt-fading procedure that inserts a pause between the SD and the prompt, starting at 0 seconds, so the learner can respond before the prompt is given.
Time delay fades prompts by changing when the prompt is given, not what kind of prompt it is. Teaching starts with 0-second delay trials: the RBT presents the SD and gives the prompt at the same moment, so the learner responds correctly. Then the RBT waits a short time before prompting. If the learner responds correctly before the prompt, the response is independent.
There are two main forms:
- Constant time delay: after a set number of 0-second trials, the delay jumps to a fixed length, such as 4 seconds, and stays there.
- Progressive time delay: the delay is increased gradually, for example 0, 1, 2, 3, then 4 seconds, as the learner succeeds.
Time delay is an errorless method because the prompt is available before the learner has time to make a mistake. It works best when the learner will wait for the prompt instead of guessing. Plans specify what to do if the learner responds incorrectly before the prompt, such as treating it as an error and using error correction.
The RBT counts the delay accurately, gives the planned prompt at the end of the delay, and records whether each response was before (independent) or after (prompted) the prompt.
Example and non-example
| Example | The RBT says "What color?" while holding a yellow block and immediately says "yellow" for the client to echo. After two sessions, the RBT asks and waits 3 seconds; the client says "yellow" before the model. |
|---|---|
| Non-example | The time between the client finishing one trial and the RBT starting the next is the intertrial interval, not a prompt delay. |
Don't confuse it with
| Latency | Latency is the measured time from the SD to the start of a response; time delay is the planned wait before a prompt is given. |
|---|---|
| Intertrial interval | The intertrial interval is the pause between trials; time delay is a wait within a trial before prompting. |
Test yourself
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Question 1Over several weeks, an RBT gradually stops using the 3-second time delay written in a client's plan and starts prompting immediately on every trial. What is this gradual departure from the written procedure called?
Show answer
B: Treatment drift. Treatment drift is a gradual change in how an intervention is carried out so that it no longer matches the written plan. It lowers procedural fidelity, often without the implementer noticing.
- A: Stimulus fading is a planned, gradual removal of an added stimulus prompt, not an unplanned change.
- C: Observer drift is a change in how a behavior definition is applied when recording, not in how the intervention is delivered.
- D: Reactivity is a change in behavior caused by being observed.
Task A.8 · 40-hour curriculum section E
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Question 2For a new target, a plan uses errorless teaching with a 0-second prompt delay. When should the RBT give the prompt?
Show answer
A: At the same time as the instruction, or immediately after it. A 0-second prompt delay means the prompt comes right with the instruction, so the client responds correctly from the start. The delay is increased later as the plan directs.
- B: Waiting before prompting is a later step in time delay, not a 0-second delay.
- C: Prompting after errors is error correction; errorless teaching prompts before an error can happen.
- D: The prompt is given with the instruction once the client is attending, or it will not help.
Task C.3 · 40-hour curriculum section E
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Question 3A child holds out an empty cup at lunch. The plan says to wait about 3 seconds with an expectant look before prompting "more juice." What is the purpose of the wait?
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D: To give a chance to request without a prompt. A brief expectant pause is a form of time delay. It gives the learner a chance to respond on their own before the prompt, which supports moving from prompted to independent mands.
- A: The wait is short, and the goal is to use the child's motivation, not reduce it.
- B: Waiting is not a punisher; it is a chance to respond independently.
- C: Holding out the cup already shows motivation; the wait is about independence.
Task C.4 · 40-hour curriculum section E
Answer every question to see your score.
On the RBT exam
This term belongs to task C.7 Prompting and prompt fading in content area C, Behavior Acquisition, which is 19 of the 75 scored questions.