Patricia Munson Doyle

System of Least Prompts: A Literature Review of Procedural Parameters

This manuscript describes an instructional strategy, system of least prompts, and reviews the use of the procedure in the applied research literature. The literature is analyzed in terms of the populations for which the procedure has been used, the type of skills that have been taught with the procedure, and the results when the procedure was employed. The literature also is described in terms of previously identified parameters of the system of least prompts including (a) the number and type of prompts included in the least-to-most assistance prompt hierarchies, (b) the presentation of the target stimulus at each prompt level, (c) use of a fixed response interval, and (d) the delivery of reinforcement following correct prompted and unprompted responses. Summary statements and recommendations about future use and research are included.

Constant time delay with discrete responses: A review of effectiveness and demographic, procedural, and methodological parameters☆

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.

Review of Comparative Studies in the Instruction of Students with Moderate and Severe Handicaps

Systematic intructional strategies that investigators have used with students who display moderate to severe handicaps were identified and defined. The investigations which directly compared two or more strategies were analyzed, and summary statements/recommendations about the relative effectiveness and efficiency of the strategies were made. Analyzing the effectiveness of the procedures involved determining which strategies successfully taught skills to subjects. The efficiency of the strategies was analyzed on measures which indicated the skills were taught in a productive and timely manner (i.e., trials to criterion, sessions to criterion, errors to criterion, direct instruction time). Recommendations for future research and practice include (a) conduct more studies comparing the effectiveness and efficiency of instructional strategies, (b) conduct investigations of the specific variables of single strategies to identify the most efficient use of each procedure, (c) expand the efficiency measures to assess whether students learn information not directly targeted for instruction, and (d) conduct research to determine which strategy is best to use with given types of students and skills.

Comparison of Response Prompting Procedures in Teaching Numeral Identification to Autistic Subjects.

This investigation compared the effectiveness and efficiency (sessions, trials, percentage of errors, direct instructional time through criterion, and incidental information learned) of constant time delay and system of least prompts in teaching students with autism to name numerals. Two sessions were provided each day; one with constant time delay and one with system of least prompts. Two students learned 16 numerals, and one student did not learn any numerals with these two procedures. The parallel treatments design was used to assess the effects of the two instructional strategies. The results indicate that both procedures were effective in raising responding to criterion levels for two subjects. The constant time-delay procedure was more efficient than the system of least prompts procedure in terms of sessions, trials, percentage of errors, and direct instructional time through criterion.

Teaching Chained Tasks in Dyads Acquisition of Target and Observational Behaviors

This investigation used a multiple probe design to evaluate the use of a constant time delay procedure in a small group instructional arrangement. Two pairs of two students (i.e., dyads) with moderate mental retardation were taught domestic and vocational chained tasks. Tasks for each dyad were divided so that one student of the dyad was taught the first part of the task, and the other student was taught the second part. Interactions between members of each dyad were specifically prompted so that students delivered both antecedent (i.e., attentional cue) and consequent (i.e., reinforcement) events to their dyad member. Students observed each other learning their respective parts of the task and then were assessed on their ability to perform both parts of the task (i.e., the part taught directly and the part taught to the other member of the dyad). The results indicate that (a) constant time delay was effective in teaching chained tasks in dyads, and (b) all students learned a substantial amount of the tasks that they were not directly taught but that they observed being taught to the other member of their dyad. These findings are discussed in terms of designing effective and efficient instruction for students with moderate handicaps.

Effects of presenting incidental information in consequent events on future learning

The effects of presenting future target stimuli in the consequent event following correct responses to current target stimuli were examined in two experiments teaching eight students with moderate handicaps to name photographs. In Experiment I, progressive time delay was used to teach two sets of photographs. During instruction, correct responses to one set of stimuli resulted in praise and presentation of the printed word for the person in the photograph (future condition). In the second set, a correct response was followed by praise alone (non-future condition). After establishing criterion level performance on both sets of photographs, students were taught to read the printed word from each of the two sets. Experiment II was a systematic replication of Experiment I. Four students from a different classroom also were taught to name two sets of photographs. An adapted alternating treatments design was used in each experiment. The results indicated that (a) all students learned to name the photographs; (b) presentation of future target stimuli (words) in consequent events resulted in seven of the eight students learning to read some of the words; and (c) the total number of sessions, trials, errors, and percentage of errors

Teaching chained skills in a non-school setting using a divided half instructional format

This investigation evaluated the use of dyadic instructional arrangements in teaching chained skills to four students with moderate mental retardation. Each instructional dyad consisted of two students. Each of the three cooking skills was divided into two equal parts, and each student in a dyad received direct instruction on one part of the task analysis during each instructional session. During the following session, the two parts were reversed and a student received instruction on the second part. A constant time delay procedure was used to teach the targeted skills in an off-campus setting. A multiple probe design across skills and replicated across students evaluated the effectiveness of the instructional procedure and teaching arrangement. Results indicate that each of the four students learned the three cooking skills. Implications for future research are discussed.

Comparison of Progressive Time Delay and Transition-Based Teaching with Preschoolers Who Have Developmental Delays

A progressive time delay procedure in one-to-one instructional sessions using massed-trial presentation was compared to transition-based teaching that involved distributed trials presented during transitions from one activity to another. Four preschool children with developmental delays were taught to read words and name letters/numerals and to produce manual signs for photographs. The classroom teacher conducted one daily massed-trial session with each student using progressive time delay for a set of behaviors, and provided an equal number of distributed trials at transition times to each student with a transition-based teaching procedure for another set of behaviors. The procedures were compared on the number of children meeting criterion (effectiveness) and on the number of trials and errors to criterion and the percentage of errors to criterion (efficiency). The parallel treatments design was used to evaluate the two instructional strategies. The results indicated that (a) both procedures were implemented reliably, (b) both procedures were effective in establishing criterion level performance, and (c) no substantial differences existed on the efficiency measures, although the number and percentage of errors were slightly higher for 3 of the 4 children with the transition-based teaching procedure. Implications for practice and future research are described.

EMBEDDING EXTRA STIMULI IN THE TASK DIRECTION: EFFECTS ON LEARNING OF STUDENTS WITH MODERATE MENTAL RETARDATION

This investigation examined the acquisition of target and nontarget stimuli by 4 students with moderate mental retardation. Students were taught to name photographs of foods (target stimuli) using a progressive time delay procedure. In addition, the grocery departments where foods could be found in a local supermarket (nontarget stimuli) were presented as part of the discriminative stimulus. A multiple probe design across photographs and replicated across students was used to assess experimental control of both target and nontarget stimuli. The results indicated that (a) progressive time delay was effective in teaching 12 target photographs to 3 students and 6 photographs to 1 student, (b) presentation of the nontarget grocery department as part of the discriminative stimulus was effective in increasing the percentages of correct responding to these stimuli across all students, and (c) some generalization in the percentage of correct responding to the target and nontarget stimuli occurred in the natural supermarket setting.

Comparison of Predictable and Unpredictable Trial Sequences during Small-Group Instruction

The use of predictable (round robin) and unpredictable (random) trial sequences during small-group instruction was evaluated in three experiments in teaching word and abbreviation identification to four students with learning disabilities; a fifth student participated in part of Experiment I before moving to another school. In Experiment I, a progressive time-delay procedure was used to teach word reading in a small group, and the effects of a single-trial, predictable sequence was compared to a single-trial, unpredictable sequence. In Experiment II, a progressive time-delay procedure also was used to teach abbreviation identification in a small group, and the effects of a multiple-trial, predictable sequence was compared to a multiple-trial, unpredictable sequence. In Experiment III, a model-test procedure was used in a small group, and the effects of the multiple-trial, predictable sequence was compared to the single-trial, unpredictable sequence. An adapted alternating-treatments design was used in all experiments. Results indicate that the progressive time-delay procedure was reliably implemented and was effective in establishing criterion-level responding by all group members. Students also learned words taught to other students through observation. In Experiment I, the two trial sequences did not differ substantially, and in Experiment II mixed effects were found. With the model-test procedure in Experiment III, two students initially produced higher levels of correct responding in the multiple-trial, predictable sequence; however, no substantial differences were found in observational learning. Across all investigations, no consistent effects of the trial presentation methods were noted.