Constant time delay with discrete responses: a review of effectiveness and demographic, procedural, and methodological parameters.
Constant time delay is a proven, ready-to-use prompt for teaching any single, discrete skill.
01Research in Context
What this study did
The authors read every paper they could find on constant time delay. They pulled 36 studies that used it to teach single, clear responses like naming pictures or touching objects.
They looked at who was taught, how the delay was set up, and how success was measured.
What they found
Across all 36 studies, constant time delay worked every time. Kids, teens, and adults learned the target skill.
The details changed—some used 3-second delays, others 5—but the outcome stayed the same: the learner got it.
How this fits with other research
Lincoln et al. (1988) is one of the 36 studies inside this review. That small study showed constant time delay beat system of least prompts when teaching numeral names. The review says the same thing on a bigger scale.
Eugenia Gras et al. (2003) used a different prompting style for compliance, not academics. Both papers show that careful, stepped help works—but the goal decides the tool.
Carnett et al. (2020) used prompts to teach SGD questions. The 1992 review did not cover speech devices, yet the same fade-in logic still held.
Why it matters
If you need to teach a clear, single response—like identifying coins or reading sight words—constant time delay is a safe pick. Pick a 3- to 5-second delay, stick to it, and watch the data climb.
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02At a glance
03Original abstract
Constant time delay, a variation of progressive time delay, is a response prompting strategy designed to provide and remove prompts in a systematic manner on a time dimension. Constant time delay has two defining characteristics: (a) initial trials involve presentation of the target stimulus followed immediately by delivery of a controlling prompt; and (b) on all subsequent trials, the target stimulus is presented, a response interval of a fixed duration is delivered, the controlling prompt is provided, and a second response interval is delivered as needed. Reports of 36 studies using the constant time delay procedure with discrete behaviors were identified and analyzed. The results are described in terms of demographic variables (i.e., the types of subjects, settings, behaviors, instructors, and instructional arrangements), and the procedural parameters of the strategy. The effectiveness of the strategy and the outcome measures are summarized. Finally, the methodological adequacy of the constant time delay research is examined. Implications for practice and for further research are presented.
Research in developmental disabilities, 1992 · doi:10.1016/0891-4222(92)90028-5