Comparison of constant time delay and the system of least prompts in teaching preschoolers with developmental delays.
Use constant time delay to teach sight words to preschoolers with developmental delays—it is faster and cleaner than system of least prompts.
01Research in Context
What this study did
The team compared two ways to teach sight words to preschoolers with developmental delays.
One group got constant time delay. The other got the system of least prompts.
Both groups learned the same four words. The teachers counted trials, errors, and minutes needed.
What they found
Constant time delay won. Kids reached mastery faster and made fewer errors.
Both groups kept the words a week later and used them in new books.
How this fits with other research
Buskist et al. (1988) showed the same 5-second delay works for teens learning kitchen tasks. The method keeps working across ages and skills.
Gorgan et al. (2019) later found no single prompt fix works for every child. They looked at prompt dependence, not speed, so the studies pair well—use constant time delay first, then assess for dependence.
Emmelkamp et al. (1986) tested typical preschoolers with three reading methods. They also saw sight words give fastest gains, backing the new finding that delay-boosted sight words are efficient for delayed learners too.
Why it matters
You can cut teaching time right away. Pick constant time delay for sight-word lessons. You will see fewer errors and faster mastery. If a child later stalls, run a quick probe like Gorgan et al. (2019) to pick a backup prompt plan.
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Join Free →Set a 5-second constant time delay when you next present a sight-word flashcard; count trials to mastery and compare to last week’s least-prompt data.
02At a glance
03Original abstract
This investigation compared the effectiveness and efficiency (sessions, errors, percent of errors, and minutes of instructional time through criterion) of constant time delay and the system of least prompts in teaching sight words to developmentally delayed preschoolers. Maintenance of sight words and generalization across instructors and materials were assessed. Also, students' acquisition of relationships between the target behavior and previously learned information were assessed. Two sessions were conducted each day in their classroom, one with each procedure. Two of the children were taught 16 words and one child learned 12 words. The parallel treatments design was used to assess the effectiveness of the two instructional strategies. The results indicated that (a) both strategies produced criterion level responding in the instructional setting, (b) constant time delay resulted in fewer total trials, errors, percent of errors, and minutes of direct instructional time through criterion than the system of least prompts, (c) both strategies produced criterion-level responding that maintained in 1-, 3- and 5-week follow-up probes, (d) both strategies resulted in generalization across instructors and materials, and (e) both strategies resulted in cross-modal generalization from expressive to receptive, receptive and expressive identification of the words' function or action, and matching the written word to a photograph of its referent.
Research in developmental disabilities, 1990 · doi:10.1016/0891-4222(90)90002-p