Setting
The study took place in an office on the campus of a public high school in the United States.
Study sample
This study included three students (Daniel, Karen, and Teresa) with intellectual disability. Daniel, a 20-year-old male, had Down syndrome and moderate intellectual disability; his IQ was not provided by the study authors. Karen, an 18-year-old female, had moderate intellectual disability and an IQ of 41, according to the Universal Nonverbal Intelligence Test. Teresa, an 18-year-old female, had severe intellectual disability and an IQ of 30, according to the Leiter International Performance Scale–Revised.
Intervention
Three separate multiple probe design experiments (one for each student) were used to measure the effectiveness of SLP across three office-related tasks: organizing a binder, collating and stapling papers, and preparing a letter. To assist students to successfully complete these tasks, the SLP intervention used a series of three prompts: 1) a verbal prompt, 2) a video prompt, which involved visual modeling of the task on an iPhone, and 3) a physical prompt. The interventionist for the study was a researcher who had visited the students’ classroom several times prior to the study. The researcher gave the instruction to begin the task and waited 5 seconds. If the participant did not begin the step, completed the step incorrectly, or took more than 10 seconds to complete the step, the researcher gave a prompt. The researcher provided verbal praise after each independent correct response. Once the participant had achieved 100% correct independent responses for one session, praise was “thinned” and given on an average of every third independent correct response during each session. Then it was further thinned and only provided at the end of the task. The intervention sessions took place in the morning for 10 to 20 minutes for each student. The number of intervention sessions ranged from 5 to 11, depending on the time that the students took to reach the criteria.
Comparison
During baseline sessions, students were directed to complete each specific step required to organize a binder, collate and staple papers, or prepare a letter. If a student did not begin the step within 5 seconds, incorrectly completed a step, or did not complete the step within 10 seconds, the researcher would block the student’s view of the task with a divider and complete that step, then remove the divider and instruct the student to complete the next step. The researcher gave verbal praise for each independent correct response, but no prompts were provided during these sessions.