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Generalized use of a handheld prompting system
Research in Developmental Disabilities 28 (2007) 397–408
Generalized use of a handheld prompting system David F. Cihak a,*, Kelby B. Kessler b,1, Paul A. Alberto b,1 a
The University of Tennessee, Theory & Practice in Teacher Education, Special Education Instructional Program, A412 Claxton Complex, Knoxville, TN 37996-3442, USA b Georgia State University, Educational Psychology & Special Education, P.O. Box 3979, Atlanta, GA 30302-3979, USA Received 21 March 2006; received in revised form 11 April 2006; accepted 2 May 2006
Abstract This study determined the effectiveness of a commercially produced handheld computer, as a prompting system in facilitating the generalization and increasing the probability of long-term maintenance of vocational skills by adolescents with moderate intellectual disabilities. Four students successfully used the system in learning a task and then generalized the use of the prompting system to complete increasingly more complex tasks. Task performance was maintained at a 100% level for up to 9 weeks. # 2006 Elsevier Ltd. All rights reserved. Keywords: Severe disabilities; Vocational instruction; Community instruction; Assistive technology
The importance of shifting the source of stimulus control away from teachers to the student has led to investigations of antecedent-based strategies. Two such strategies are the use of picture prompts (e.g., Cihak, Alberto, Taber, & Kessler, 2004; Connis, 1979; Wilson, Scheppis, & MasonMain, 1987) and self-operated auditory prompts (e.g., Alberto, Sharpton, Briggs, & Stright, 1986; Briggs et al., 1990). These strategies have been successful in facilitating acquisition of skills, demonstrating maintenance, and providing a degree of student independence. Once a student was trained in the use of a picture prompts or self-operated auditory prompts and demonstrated competency in performing an initial skill, a student’s ability to generalize the use of the prompt system to non-trained skills is a pragmatic instructional concern. Wacker and Berg (1983, 1984) reported that adolescents with severe intellectual disabilities generalized the use of picture prompts across similar tasks. Likewise, Alberto et al. (1986) reported the use of
* Corresponding author. Tel.: +1 865 974 4156; fax: +1 865 974 8718. E-mail addresses: [email protected] (D.F. Cihak), [email protected] (P.A. Alberto). 1 Tel.: +1 404 651 2310. 0891-4222/$ – see front matter # 2006 Elsevier Ltd. All rights reserved. doi:10.1016/j.ridd.2006.05.003
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auditory prompts by adolescents with severe intellectual disabilities in generalizing task mastery across similar skills. In 1985, Wacker, Berg, Berrie, and Swatta demonstrated that generalization occurred across dissimilar tasks following the use of picture prompts with no additional training in the use of the prompting system, substantially reducing task training requirements. Similarly, Briggs et al. (1990) demonstrated that generalization of the use of auditory prompts occurred across dissimilar tasks also reduced the amount of training required. A third antecedent-based strategy that shifts the source of stimulus control away from teachers to the student is a handheld computer prompting system (Davies, Stock, & Wehmeyer, 2002a, 2002b, 2003). The handheld computer is one of the latest devices in technology that has been demonstrated to be an appropriate device to assist individuals with disabilities functioning at school, work, home, and community settings (Ferguson, Myles, & Hagiwara, 2005; Furniss et al., 2001). A small handheld computer allows access to picture prompts, auditory prompts, and video clips. The most obvious advantages of the handheld computer are its compact size and portability. Moreover, handhelds require minimal storage space and students can take them almost anywhere. One way to distinguish between handheld computer technologies is between commercially available devices and those that are custom made for an individual person (Cook & Hussey, 2002). The term commercially available refers to devices that are mass-produced. These include commercial devices designed for the general population. Increasingly, commercial products are being designed according to the principles of universal design. Universal design is the design of technologies to be usable by all people, to the greatest extent possible, without the need for adaptation or specialized design. In this approach, features are built into the product (e.g., various display options—visual, auditory; alternatives to reading text-icons, pictures), which makes a product more accessible to individuals with disabilities. This is much less expensive than adapting a product after production in order to meet the needs of an individual with a disability. If commercially available devices cannot meet an individual’s needs, it may be modified. However, when modification or commercial devices are not appropriate, it is necessary to design one specifically for the task-at-hand. This approach results in a custom device. Since custom products are not mass-produced, a custom device costs are much higher because it is a special product or a ‘‘one of a kind’’ and the costs of development must be recovered from the smaller production. Davies et al. (2002a, 2002b, 2003) used a custom-made handheld computer and software to increase students with mild to severe intellectual disabilities independent performances of functional tasks. Students required fewer prompts and external supports to complete the tasks using the handheld computer compared to when students did not use the handheld. Riffel et al. (2005) further indicated that students’ with developmental delays reduced the amount of time needed to complete tasks and increased work productivity when using a custom-made device. Moreover, Ferguson et al. (2005) indicated that an adolescent with Asperger’s Syndrome decreased adult reliance to complete tasks at home and at school. Although using a handheld computer to increase task completion across settings has proven successful, generalization across different tasks and maintenance of skill acquisition were not examined in the aforementioned studies. Davies et al. (2003) noted that further research was needed to assess the effectiveness of handheld computers as a prompting system across a variety of tasks, domains, and ecologically valid work and employment settings. The purpose of this study was to determine the effectiveness of a commercially produced handheld computer, as a prompting system to facilitate the generalization of increasingly complex vocational skills and to increase the probability of long-term maintenance of skills by adolescents with moderate intellectual disabilities.
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1. Method 1.1. Participants Four students Jose, Curt, Nate, and Kim were selected to participate based on the following: (a) willingness to participate, (b) level of cognitive functioning within the moderate intellectual disability range, (c) current participation in a high school program with regularly scheduled community-based instruction, (d) no sensory deficits, (e) no prior training with the targeted tasks selected, (f) parental permission, and (g) the student’s verbal agreement to participate. Jose and Kim were 19 year old with a full-scale IQ of 45 and 50, respectfully. Curt and Nate were 18 years old with a full-scale IQ of 43 and 40, respectfully. IQ’s were assessed using the Wechsler Intelligence (Wechsler, 1991) for Children for Jose, Curt, and Nate. The Standford Binet (Thorndike, Hagen, & Sattler, 1986) was used to assess Kim. 1.2. Settings Pretraining instruction using the handheld computer occurred in each student’s school resource classroom. Baseline, handheld prompting, and maintenance phases occurred during community-based instruction (CBI) in a three community settings: grocery store, department store, and restaurant. Stores and restaurant were selected because of the convenient location to the students’ neighborhood school. Community instruction for Jose and Curt was at a grocery store, Nate at a restaurant, and Kim at a department store. 1.3. Materials A Kodak DX3600 Zoom digital camera was used to digitally photograph each task analyzed step. Digital photos were then downloaded into an Axium X30 handheld computer that was used to deliver the picture and auditory prompts. The Axium X30 was selected since it was the least expensive device that allowed capabilities of photo display and to record narration. Picture Perfect software was used to develop the picture and auditory prompts task sequence. The Picture Perfect software was selected due to its relative inexpensive price and capabilities of creating a relatively easy picture and auditory prompting system. Students placed the handheld computer in a pack fastened to their waist with a small headphone that attached around the ear. The headphone wire was worn under the uniform to reduce interference during task engagement. Students advanced the prompting system by pressing an arrow hardware button. 1.4. Tasks Four tasks, which increased in task complexity, were selected for each student was relevant to their IEP goals. Table 1 displays the task analysis and the number of steps required to complete each task. Jose and Curt’s tasks included gathering carts (5-steps), stocking milk (7-steps), vacuuming (17-steps), and making sub-rolls (20-steps). Nate self-prepped (4-steps), prepared broccoli (13-steps), skewered shrimp (15-steps), and prepared tea (18-steps). Kim straightened mushrooms (6-steps), stocked bananas (10-steps), stocked pineapples (14-steps), and cleaned a fitting room (17-steps).
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Table 1 Task analysis of skills Functional skill
Number of steps Steps task analysis task 4 5 6
Socking milk
7
Stocking bananas
10
Preparing broccoli
13
Stocking pineapples
14
Skewering shrimp
15
Cleaning fitting room 17
Vacuuming
17
Preparing tea
18
Making sub-rolls
20
(1) Put on apron; (2) wash hands; (3) get gloves, (4) put on gloves (1) Go outside; (2) go to cart corral; (3) get two carts, (4) push two carts together; (5) push carts to front of store (1) Go to produce; (2) go to salad section; (3) go to mushroom display; (4) match up the mushrooms; (5) move the mushroom packages to the front; (6) align the row of mushrooms (1) Go to milk section; (2) go to red labeled milk; (3) move the milk from bottom shelf to shelf above; (4) find date; (5) put older date in front; (6) put recent date in back; (7) align milk (1) Get cart; (2) go to produce stockroom; (3) ask co-worker for banana box; (4) take bananas to display; (5) align bananas; (6) open box; (7) put bananas in empty spaces; (8) close box; (9) return banana box to stockroom; (10) return box (1) Get scale; (2) get bags with today’s date; (3) get two pans; (4) go to cooler; (5) get broccoli; (6) pour broccoli into pans; (7) bag broccoli; (8) weigh broccoli on 4-oz scale; (9) put bagged broccoli into pan; (10) write date on bag; (11) open cooler; (12) put broccoli on shelf; (13) put away materials (1) Get cart; (2) go to produce; (3) go to pineapple section; (4) get pineapples from bottom shelf; (5) put pineapples in cart; (6) remove all pineapples; (7) put pineapples stem-side up; (8–14) shelf pineapples (1) Get pans; (2) get box of skews from brown box; (3) fill one pan with water; (4) put skewers in pan; (5) go to cooler; (6) get frozen shrimps; (7) put shrimp in large pan; (8) get shrimp and push skewer through tail; (9) push skewer on shrimp head; (10) put four shrimps on skewer; (11) put skewer shrimp into pan; (12) go to cooler; (13) put pan in meat section of cooler; (14) put away materials; (15) wipe down table (1) Go to fitting room; (2) pick up clothes; (3) put clothes table; (4) pick up hangers; (5) put hangers on rack; (6) pick up large pieces of garbage and put in trash; (7) go to breakroom; (8) get vacuum; (9) go to fitting room; (10) unwind cord; (11) plug into socket; (12) turn on vacuum; (13) pull vacuum back; (14) vacuum rooms; (15) unplug vacuum; (16) wrap cord; (17) return vacuum to breakroom (1) Go to breakroom; (2) get vacuum; (3) take vacuum to front; (4) set vacuum next to water machine; (5) unwind cord; (6) plug into socket; (7) turn on vacuum; (8) put foot on base of vacuum; (9) pull vacuum back; (9) vacuum mats; (10) unplug vacuum; (11) wrap cord to the base; (12) wrap cord around top knob; (13) continue wrapping cord; (14) snap plug onto cord; (15–17) straighten mats; (18) empty trash; (19) return vacuum to breakroom (1) Get tea filter; (2) get paper filter; (3) put filters together; (4) get tea bag; (5) pour tea grounds; (6) put filter in brewer; (7) remove tea lid; (8) push switch on the left; (9) get pitcher; (10) get sugar; (11) pour sugar into pitcher; (12) fill pitcher with hot water; (13) stir; (14) pour sugar water into brewer; (15) fill pitcher with tea; (16) pour tea into brewer; (17) pour tea into pitchers; (18) take fill pitchers to tea station (1) Get apron; (2) put on apron; (3) get hairnet; (4) put on hairnet; (5) wash hands; (6) get gloves; (7) put on gloves; (8) get cart; (9) go to cooler; (10) get box labeled Hoagie; (11) put box on cart; (12) get rack; (13) get key; (14) open box with key; (15) get five-slot pans; (16) put pan on table; (17) take rolls out of box; (18) put five rolls on one side; (19) put five rolls on the other side; (20) put pan of rolls on the rack
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Self-preparation Gathering carts Straighten mushrooms
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1.5. Experimental design A multiple-probe across tasks (Barlow & Hersen, 1984) complexity with maintenance was used to determine the efficacy the use of the handheld prompting system and student’s independent performance. Each student was assigned four tasks in which the number of task analyzed steps increased. For each task, three phases included baseline, acquisition of handheld prompting instruction, and maintenance phases. Prior to baseline a pre-training period occurred during which the students were taught to operate the handheld prompting system, to select the different tasks to perform, to press the hardware button to advance to the next step of the task analysis and to follow the recorded directions. 1.6. Data collection Data were collected through use of a prepared data sheet designed to record the controlled presentation of tasks analyzed chains. Event recording procedures were used to record each step as independently performed or incorrectly performed. Data were collected and recorded for each session which composed of one instructional trial. 1.7. Experimental procedures 1.7.1. Pretraining Prior to baseline, students’ participated in a pretraining period. For the first phase of pretraining, students were instructed how to operate the handheld computer. They were instructed to physically turn on the device, to wear the headphones, to select color-cued icons representing the different tasks or jobs to perform, and to select a color-cued hardware button to advance to the next step of the task analysis. In the second phase, students were required to turn-on the device and select a prerecorded icon, which caused a popped-up window to occur with a familiar picture plus auditory prompt, and to follow each instruction. Students also were required to press the hardware button to display the next direction. The prerecorded device instructed students to complete a two-step task familiar to students and normally associated with their morning classroom routine. Students were instructed to ‘‘close the door and hang up your coat,’’ or ‘‘sit down at the table and pick-up your pencil.’’ Each student was required to reach a criterion of 100% accuracy for two consecutive sessions. 1.7.2. Baseline Each session during baseline, as well as the succeeding phases, consisted of one opportunity for completion of all the steps in a task. During baseline, the students were presented with all of the materials required for the task. For each task, students were given a single verbal cue for task performance (e.g., ‘‘go gather the carts, prepare the broccoli, go clean the fitting room’’). No further assistance, instruction, or feedback was provided. 1.7.3. Handheld prompting procedures Students were provided with the handheld prompting system and headphones and instructed to turn on the device. After the device was activated, a pop-up window with an icon of the targeted task was displayed. After the student pressed the icon, a picture and auditory prompt of the first step of the task was displayed. Students then pressed the color-cued hardware button to advance to the next step of the task. As students followed the task sequences, a least-to-most prompt
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hierarchy was used until the student correctly performed the step. A 3-s interval between each prompt level was implemented. The least-to-most prompt hierarchy consisted of the following levels across instructional trials: (a) verbal prompt (e.g., ‘‘Did you hear and see what you are suppose to do?’’), (b) gesture (e.g., pointing to picture prompt on the handheld device), (c) gesture plus verbal explanation (e.g., pointing to the picture prompt and providing a verbal explanation), (d) modeling plus verbal explanation (e.g., pointing to the picture prompt, providing a verbal explanation, and demonstrating the correct response), and (e) physical assistance plus verbal explanation (e.g., holding the student’s wrist, pointing to the picture prompt, providing a verbal explanation, and physically assisting the student the correct response). Criterion for completion of this phase was 100% independent performance for three consecutive sessions. 1.7.4. Maintenance procedures Follow-up probes were collected 9 weeks after the student meet acquisition criterion on the fourth task. Follow-up probes occurred in the community setting where the student was initially trained. Follow-up probes were collected to determine if the initial instructional affected the student’s performance over time. 1.8. Reliability Interobserver reliability data and procedural reliability data were collected simultaneously by the primary investigator and the classroom teacher. Interobserver and procedural reliability data were collected during 33% of baseline and each concurrent phase. Observers independently and simultaneously recorded the number of steps the student performed independently or the required prompt and response time. Interobserver agreement was calculated by dividing the number of agreements of student responses by the number of agreements plus disagreements and multiplying by 100. Interobserver reliability ranged from 95 to 100%, with a mean of 98% agreement. The mean interobserver reliability agreement for each student across conditions was Jose, 100%; Curt, 96%; Nate, 100%, and Kim, 97%. Procedural integrity measures check the investigator’s performance by using the correct prompting hierarchy and response time. The classroom teacher was trained using an itemized checklist that listed the task-analyzed steps of each task and the level of prompt. The teacher was considered successfully trained after completing 100% of the checklist for three consecutive trials. The procedural agreement level was calculated by dividing the number of observed teacher behaviors by the number of planned teacher behaviors and multiplying by 100 (Billingsley, White, & Munson, 1980). Procedural reliability ranged from 96 to 100%, with a mean of 99%. The mean procedural reliability agreement for each student across conditions was: Jose, 99%; Curt, 100%; Nate, 96%; Kim 100% 2. Results The percentage of steps performed independently for students across increasing task complexity is presented in Figs. 1–4. Overall, students’ independent mean performance during baseline was 7% (range 2–17%) across tasks. All students increased independent task performance using the handheld prompting systems to a mean of 69% (range 62–74%) across tasks. Students also maintained all four skills 9 weeks later with 100% independence.
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Fig. 1. Jose’s percentage of steps performed independently across tasks.
2.1. Jose Fig. 1 displays the percentage of steps performed independently across tasks. The mean percentage of independent performance during baseline for gathering carts were 13%, stocking milk was 11%, vacuuming was 7%, and making sub-rolls was 2%. Using the handheld prompting device, the mean percentage of steps performed independently increased to 68% for gathering carts, 70% for stocking milk, 65% for vacuuming, and 70% for making sub-rolls. Jose also maintained 100% performance 9 weeks later. 2.2. Curt Fig. 2 displays the percentage of steps performed independently across tasks. The mean percentage of independent performance during baseline for gathering carts were 4%, stocking
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Fig. 2. Curt’s percentage of steps performed independently across tasks.
milk was 7%, vacuuming was 4%, and making sub-rolls was 3%. Using the handheld prompting device, the mean percentage of steps performed independently increased to 66% for gathering carts, 72% for stocking milk, 67% for vacuuming, and 76% for making sub-rolls. Curt also maintained 100% performance 9 weeks later. 2.3. Nate Fig. 3 displays the percentage of steps performed independently across tasks. The mean percentage of independent performance during baseline was 10% for self-prepping, 10% for preparing broccoli, 5% for skewering shrimp, and 8% for preparing tea. Using the handheld prompting device, the mean percentage of steps performed independently increased to 71% for
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Fig. 3. Nate’s percentage of steps performed independently across tasks.
self-prepping, 62% for preparing broccoli, 69% for skewering shrimp, and 64% for making tea. Nate also maintained 100% performance 9 weeks later.
2.4. Kim Fig. 4 displays the percentage of steps performed independently across tasks. The mean percentage of independent performance during baseline for straightening mushrooms was 17%, stocking bananas was 4%, stocking pineapples was 12%, and cleaning the fitting room was 5%. Using the handheld prompting device, the mean percentage of steps performed independently increased to 74% for straightening mushrooms, 66% for stocking bananas, 65% for stocking pineapples, and 85% for cleaning the fitting room. Kim also maintained 100% performance 9 weeks later.
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Fig. 4. Kim’s percentage of steps performed independently across tasks.
3. Discussion The purpose of this study was to demonstrate the use of a commercially produced handheld computer, as a prompting system, to facilitate generalization across increasingly complex tasks and to increase the probability of skill maintenance by adolescents with moderate intellectual disabilities. The results of this study parallel the findings of Wacker et al. (1985) and Briggs et al. (1990) research in which picture prompts and auditory prompts were used to increase generalization across dissimilar and increasing complex tasks without additional training. This study confirms previous research (Davies et al., 2002a, 2002b, 2003; Ferguson et al., 2005; Furniss et al., 2001; Riffel et al., 2005) that the use of handheld computers as a prompting system is a viable alternative prompting strategy to enhance independent performance for individuals with disabilities.
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This study extends the research literature of handheld computers by enabling students to use the handheld prompting system to learn to perform increasingly complex tasks without additional training in the operation of the prompting system. As no further training in the use of the handheld computer was needed during generalization conditions, it is noted that planned, programmed generalization occurred across tasks. Rather than relying on the ‘‘train and hope’’ strategy (Stokes & Baer, 1977), a specific plan for generalization of learning was incorporated into the instructional objective through use of the handheld prompting system. The second purpose of this study increased the probability of long-term maintenance of skills addressed by the use of the handheld prompting system. The learning of complex skills or chain tasks, the frequency of which only occurs sporadically in the natural environment, was maintained through a permanent prompt apparatus. People look up telephone numbers that we do not call frequently. People refer to recipes when preparing dishes that are only consumed occasionally. People follow instructions once a year to fill out income tax forms. The use of handheld computers as reminders when completing tasks is a natural and social valid, albeit technologically modern, means of maintaining performance. A third purpose was to use a commercially available handheld computer to enhance skill acquisition, generalization, and maintenance. The advantages of using commercially available products include lower costs, availability of operation manuals, and greater levels of technical supports. Moreover, when the universal design approach is applied, accessibility and usability of handheld computers increases. This promising technology, which promotes greater independence, can then be utilized by more individuals with disabilities. Since the professional literature recognizes that generalization and maintenance are difficult skills for students with moderate intellectual disabilities to learn, it is incumbent upon teachers and professionals to address these concerns in instructional program planning and teaching strategies. The use of a handheld computer prompting system is one way of enhancing this instructional component. With this methodology, teachers and professionals can increase the level of independence, self-sufficiency and the quality life of students with disabilities. Several limitations of this study may have affected the results and interpretations. First, task complexity was defined as increased motor responses. Tasks that also increased cognitive demands may produce differentiated outcomes. Second, the study was conducted with students who had extensive CBI experiences. Students with less extensive community experiences may require more intensive instruction to acquire, generalize, and maintain targeted skills. Third, all students demonstrated no resistant behaviors toward wearing the device and were extremely motivated using the handheld computer. Students who are less motivated or resistant to using the handheld computer may perform differently. Future research is needed to verify the results of this study and to investigate generalization across task complexity involving increase cognitive demands. Additionally, different community settings (e.g., restaurants, stores, and office buildings) and types of skills (e.g., domestic, leisure, and community) need to be investigated. Future research also should attempt to replicate these results across natural support instructors (e.g., job coach, co-worker, and parent), student characteristics, teacher to student ratio, frequency or training opportunities, and the inclusion of self-evaluation steps. References Alberto, P. A., Sharpton, W. R., Briggs, A., & Stright, M. H. (1986). Facilitating task acquisition through the use of a selfoperated auditory prompting system. The Association for Persons with Severe Handicaps, 11, 85–91.
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Barlow, D. H., & Hersen, M. (1984). Single case experimental designs: Strategies for studying behavior change (2nd ed.). Needham Heights, MA: Allyn & Bacon. Billingsley, F. F., White, O. R., & Munson, R. (1980). Procedure reliability: A rational and an example. Behavioral Assessments, 2, 229–241. Briggs, A., Alberto, P., Sharpton, W., Berlin, K., McKinley, C., & Ritts, C. (1990). Generalized use of a self-operated auditory prompt system. Education and Training in Mental Retardation, 25, 381–389. Cihak, D. F., Alberto, P. A., Taber, T. A., & Kessler, K. B. (2004). An investigation of instructional scheduling arrangements for community-based instruction. Research in Developmental Disabilities, 25, 67–88. Cook, A. M., & Hussey, S. M. (2002). Assistive technologies principles and practices. St. Louis, MO Mosby. Connis, R. (1979). The effects of sequential pictorial cues, self-recording, and praise on the job task sequencing of retarded adults. Journal of Applied Behavior Analysis, 12, 355–361. Davies, D. K., Stock, S., & Wehmeyer, M. L. (2002a). Enhancing independent task performance for individuals with mental retardation through use of a handheld self-directed visual and audio prompting system. Education and Training in Mental Retardation and Developmental Disabilities, 37, 209–218. Davies, D. K., Stock, S., & Wehmeyer, M. L. (2002b). Enhancing independent time-management skills of individuals with mental retardation using a palmtop personal computer. Mental Retardation, 40, 358–365. Davies, D. K., Stock, S., & Wehmeyer, M. L. (2003). A palmtop computer-based intelligent aid for individuals with intellectual disabilities to increase independent decision making. Research and Practice for Persons with Severe Disabilities, 28(4), 182–193. Ferguson, H., Myles-Smith, B., & Hagiwara, T. (2005). Using a personal digital assistant to enhance the independence of an adolescent with asperger syndrome. Education and Training in Mental Retardation and Developmental Disabilities, 40, 60–67. Furniss, F., Lancioni, G., Rocha, N., Cunha, B., Seedhouse, P., Morato, P., et al. (2001). VICAID: Development and evaluation of palmtop-based job aid for workers with severe developmental disabilities. British Journal of Educational Technology, 32, 277–287. Riffel, L. A., Wehmeyer, M. L., Turnball, A. P., Lattimore, J., Davies, D., Stock, S., et al. (2005). Promoting independent performance of transition-related tasks using a palmtop pc-based self-directed visual and auditory prompting system. Journal of Special Education Technology, 20(1), 5–14. Stokes, T., & Baer, D. (1977). An implicit technology of generalization. Journal of Applied Behavior Analysis, 10, 349– 367. Thorndike, R. L., Hagen, E. P., & Sattler, J. M. (1986). The Standford–Binet intelligence scale, fourth edition: Guide for administering and scoring. Chicago: Riverside. Wacker, D., & Berg, W. (1983). Effects of picture prompts on the acquisition of complex vocational tasks by mentally retarded adolescents. Journal of Applied Behavior Analysis, 16, 417–433. Wacker, D., & Berg, W. (1984). Training adolescents with severe handicaps to set up job tasks independently with picture prompts. Analysis and Intervention in Developmental Disabilities, 4, 353–365. Wacker, D., Berg, W., Berrie, P., & Swatta, P. (1985). Generalization and maintenance of complex skills by severe handicapped adolescents following picture prompt training. Journal of Applied Behavior Analysis, 18, 329–336. Wechsler, D. (1991). Wechsler intelligence scale for children, third edition manual. San Antonio, TX: Psychological Corporation Harcourt Brace Jovanovich. Wilson, P., Schepis, M., & Mason-Main, M. (1987). In vivo use of picture prompt training to increase independent work at a restaurant. The Journal of the Association for Persons with Severe Handicaps, 12, 145–150.
Generalized use of a handheld prompting system David F. Cihak a,*, Kelby B. Kessler b,1, Paul A. Alberto b,1 a
The University of Tennessee, Theory & Practice in Teacher Education, Special Education Instructional Program, A412 Claxton Complex, Knoxville, TN 37996-3442, USA b Georgia State University, Educational Psychology & Special Education, P.O. Box 3979, Atlanta, GA 30302-3979, USA Received 21 March 2006; received in revised form 11 April 2006; accepted 2 May 2006
Abstract This study determined the effectiveness of a commercially produced handheld computer, as a prompting system in facilitating the generalization and increasing the probability of long-term maintenance of vocational skills by adolescents with moderate intellectual disabilities. Four students successfully used the system in learning a task and then generalized the use of the prompting system to complete increasingly more complex tasks. Task performance was maintained at a 100% level for up to 9 weeks. # 2006 Elsevier Ltd. All rights reserved. Keywords: Severe disabilities; Vocational instruction; Community instruction; Assistive technology
The importance of shifting the source of stimulus control away from teachers to the student has led to investigations of antecedent-based strategies. Two such strategies are the use of picture prompts (e.g., Cihak, Alberto, Taber, & Kessler, 2004; Connis, 1979; Wilson, Scheppis, & MasonMain, 1987) and self-operated auditory prompts (e.g., Alberto, Sharpton, Briggs, & Stright, 1986; Briggs et al., 1990). These strategies have been successful in facilitating acquisition of skills, demonstrating maintenance, and providing a degree of student independence. Once a student was trained in the use of a picture prompts or self-operated auditory prompts and demonstrated competency in performing an initial skill, a student’s ability to generalize the use of the prompt system to non-trained skills is a pragmatic instructional concern. Wacker and Berg (1983, 1984) reported that adolescents with severe intellectual disabilities generalized the use of picture prompts across similar tasks. Likewise, Alberto et al. (1986) reported the use of
* Corresponding author. Tel.: +1 865 974 4156; fax: +1 865 974 8718. E-mail addresses: [email protected] (D.F. Cihak), [email protected] (P.A. Alberto). 1 Tel.: +1 404 651 2310. 0891-4222/$ – see front matter # 2006 Elsevier Ltd. All rights reserved. doi:10.1016/j.ridd.2006.05.003
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auditory prompts by adolescents with severe intellectual disabilities in generalizing task mastery across similar skills. In 1985, Wacker, Berg, Berrie, and Swatta demonstrated that generalization occurred across dissimilar tasks following the use of picture prompts with no additional training in the use of the prompting system, substantially reducing task training requirements. Similarly, Briggs et al. (1990) demonstrated that generalization of the use of auditory prompts occurred across dissimilar tasks also reduced the amount of training required. A third antecedent-based strategy that shifts the source of stimulus control away from teachers to the student is a handheld computer prompting system (Davies, Stock, & Wehmeyer, 2002a, 2002b, 2003). The handheld computer is one of the latest devices in technology that has been demonstrated to be an appropriate device to assist individuals with disabilities functioning at school, work, home, and community settings (Ferguson, Myles, & Hagiwara, 2005; Furniss et al., 2001). A small handheld computer allows access to picture prompts, auditory prompts, and video clips. The most obvious advantages of the handheld computer are its compact size and portability. Moreover, handhelds require minimal storage space and students can take them almost anywhere. One way to distinguish between handheld computer technologies is between commercially available devices and those that are custom made for an individual person (Cook & Hussey, 2002). The term commercially available refers to devices that are mass-produced. These include commercial devices designed for the general population. Increasingly, commercial products are being designed according to the principles of universal design. Universal design is the design of technologies to be usable by all people, to the greatest extent possible, without the need for adaptation or specialized design. In this approach, features are built into the product (e.g., various display options—visual, auditory; alternatives to reading text-icons, pictures), which makes a product more accessible to individuals with disabilities. This is much less expensive than adapting a product after production in order to meet the needs of an individual with a disability. If commercially available devices cannot meet an individual’s needs, it may be modified. However, when modification or commercial devices are not appropriate, it is necessary to design one specifically for the task-at-hand. This approach results in a custom device. Since custom products are not mass-produced, a custom device costs are much higher because it is a special product or a ‘‘one of a kind’’ and the costs of development must be recovered from the smaller production. Davies et al. (2002a, 2002b, 2003) used a custom-made handheld computer and software to increase students with mild to severe intellectual disabilities independent performances of functional tasks. Students required fewer prompts and external supports to complete the tasks using the handheld computer compared to when students did not use the handheld. Riffel et al. (2005) further indicated that students’ with developmental delays reduced the amount of time needed to complete tasks and increased work productivity when using a custom-made device. Moreover, Ferguson et al. (2005) indicated that an adolescent with Asperger’s Syndrome decreased adult reliance to complete tasks at home and at school. Although using a handheld computer to increase task completion across settings has proven successful, generalization across different tasks and maintenance of skill acquisition were not examined in the aforementioned studies. Davies et al. (2003) noted that further research was needed to assess the effectiveness of handheld computers as a prompting system across a variety of tasks, domains, and ecologically valid work and employment settings. The purpose of this study was to determine the effectiveness of a commercially produced handheld computer, as a prompting system to facilitate the generalization of increasingly complex vocational skills and to increase the probability of long-term maintenance of skills by adolescents with moderate intellectual disabilities.
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1. Method 1.1. Participants Four students Jose, Curt, Nate, and Kim were selected to participate based on the following: (a) willingness to participate, (b) level of cognitive functioning within the moderate intellectual disability range, (c) current participation in a high school program with regularly scheduled community-based instruction, (d) no sensory deficits, (e) no prior training with the targeted tasks selected, (f) parental permission, and (g) the student’s verbal agreement to participate. Jose and Kim were 19 year old with a full-scale IQ of 45 and 50, respectfully. Curt and Nate were 18 years old with a full-scale IQ of 43 and 40, respectfully. IQ’s were assessed using the Wechsler Intelligence (Wechsler, 1991) for Children for Jose, Curt, and Nate. The Standford Binet (Thorndike, Hagen, & Sattler, 1986) was used to assess Kim. 1.2. Settings Pretraining instruction using the handheld computer occurred in each student’s school resource classroom. Baseline, handheld prompting, and maintenance phases occurred during community-based instruction (CBI) in a three community settings: grocery store, department store, and restaurant. Stores and restaurant were selected because of the convenient location to the students’ neighborhood school. Community instruction for Jose and Curt was at a grocery store, Nate at a restaurant, and Kim at a department store. 1.3. Materials A Kodak DX3600 Zoom digital camera was used to digitally photograph each task analyzed step. Digital photos were then downloaded into an Axium X30 handheld computer that was used to deliver the picture and auditory prompts. The Axium X30 was selected since it was the least expensive device that allowed capabilities of photo display and to record narration. Picture Perfect software was used to develop the picture and auditory prompts task sequence. The Picture Perfect software was selected due to its relative inexpensive price and capabilities of creating a relatively easy picture and auditory prompting system. Students placed the handheld computer in a pack fastened to their waist with a small headphone that attached around the ear. The headphone wire was worn under the uniform to reduce interference during task engagement. Students advanced the prompting system by pressing an arrow hardware button. 1.4. Tasks Four tasks, which increased in task complexity, were selected for each student was relevant to their IEP goals. Table 1 displays the task analysis and the number of steps required to complete each task. Jose and Curt’s tasks included gathering carts (5-steps), stocking milk (7-steps), vacuuming (17-steps), and making sub-rolls (20-steps). Nate self-prepped (4-steps), prepared broccoli (13-steps), skewered shrimp (15-steps), and prepared tea (18-steps). Kim straightened mushrooms (6-steps), stocked bananas (10-steps), stocked pineapples (14-steps), and cleaned a fitting room (17-steps).
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Table 1 Task analysis of skills Functional skill
Number of steps Steps task analysis task 4 5 6
Socking milk
7
Stocking bananas
10
Preparing broccoli
13
Stocking pineapples
14
Skewering shrimp
15
Cleaning fitting room 17
Vacuuming
17
Preparing tea
18
Making sub-rolls
20
(1) Put on apron; (2) wash hands; (3) get gloves, (4) put on gloves (1) Go outside; (2) go to cart corral; (3) get two carts, (4) push two carts together; (5) push carts to front of store (1) Go to produce; (2) go to salad section; (3) go to mushroom display; (4) match up the mushrooms; (5) move the mushroom packages to the front; (6) align the row of mushrooms (1) Go to milk section; (2) go to red labeled milk; (3) move the milk from bottom shelf to shelf above; (4) find date; (5) put older date in front; (6) put recent date in back; (7) align milk (1) Get cart; (2) go to produce stockroom; (3) ask co-worker for banana box; (4) take bananas to display; (5) align bananas; (6) open box; (7) put bananas in empty spaces; (8) close box; (9) return banana box to stockroom; (10) return box (1) Get scale; (2) get bags with today’s date; (3) get two pans; (4) go to cooler; (5) get broccoli; (6) pour broccoli into pans; (7) bag broccoli; (8) weigh broccoli on 4-oz scale; (9) put bagged broccoli into pan; (10) write date on bag; (11) open cooler; (12) put broccoli on shelf; (13) put away materials (1) Get cart; (2) go to produce; (3) go to pineapple section; (4) get pineapples from bottom shelf; (5) put pineapples in cart; (6) remove all pineapples; (7) put pineapples stem-side up; (8–14) shelf pineapples (1) Get pans; (2) get box of skews from brown box; (3) fill one pan with water; (4) put skewers in pan; (5) go to cooler; (6) get frozen shrimps; (7) put shrimp in large pan; (8) get shrimp and push skewer through tail; (9) push skewer on shrimp head; (10) put four shrimps on skewer; (11) put skewer shrimp into pan; (12) go to cooler; (13) put pan in meat section of cooler; (14) put away materials; (15) wipe down table (1) Go to fitting room; (2) pick up clothes; (3) put clothes table; (4) pick up hangers; (5) put hangers on rack; (6) pick up large pieces of garbage and put in trash; (7) go to breakroom; (8) get vacuum; (9) go to fitting room; (10) unwind cord; (11) plug into socket; (12) turn on vacuum; (13) pull vacuum back; (14) vacuum rooms; (15) unplug vacuum; (16) wrap cord; (17) return vacuum to breakroom (1) Go to breakroom; (2) get vacuum; (3) take vacuum to front; (4) set vacuum next to water machine; (5) unwind cord; (6) plug into socket; (7) turn on vacuum; (8) put foot on base of vacuum; (9) pull vacuum back; (9) vacuum mats; (10) unplug vacuum; (11) wrap cord to the base; (12) wrap cord around top knob; (13) continue wrapping cord; (14) snap plug onto cord; (15–17) straighten mats; (18) empty trash; (19) return vacuum to breakroom (1) Get tea filter; (2) get paper filter; (3) put filters together; (4) get tea bag; (5) pour tea grounds; (6) put filter in brewer; (7) remove tea lid; (8) push switch on the left; (9) get pitcher; (10) get sugar; (11) pour sugar into pitcher; (12) fill pitcher with hot water; (13) stir; (14) pour sugar water into brewer; (15) fill pitcher with tea; (16) pour tea into brewer; (17) pour tea into pitchers; (18) take fill pitchers to tea station (1) Get apron; (2) put on apron; (3) get hairnet; (4) put on hairnet; (5) wash hands; (6) get gloves; (7) put on gloves; (8) get cart; (9) go to cooler; (10) get box labeled Hoagie; (11) put box on cart; (12) get rack; (13) get key; (14) open box with key; (15) get five-slot pans; (16) put pan on table; (17) take rolls out of box; (18) put five rolls on one side; (19) put five rolls on the other side; (20) put pan of rolls on the rack
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Self-preparation Gathering carts Straighten mushrooms
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1.5. Experimental design A multiple-probe across tasks (Barlow & Hersen, 1984) complexity with maintenance was used to determine the efficacy the use of the handheld prompting system and student’s independent performance. Each student was assigned four tasks in which the number of task analyzed steps increased. For each task, three phases included baseline, acquisition of handheld prompting instruction, and maintenance phases. Prior to baseline a pre-training period occurred during which the students were taught to operate the handheld prompting system, to select the different tasks to perform, to press the hardware button to advance to the next step of the task analysis and to follow the recorded directions. 1.6. Data collection Data were collected through use of a prepared data sheet designed to record the controlled presentation of tasks analyzed chains. Event recording procedures were used to record each step as independently performed or incorrectly performed. Data were collected and recorded for each session which composed of one instructional trial. 1.7. Experimental procedures 1.7.1. Pretraining Prior to baseline, students’ participated in a pretraining period. For the first phase of pretraining, students were instructed how to operate the handheld computer. They were instructed to physically turn on the device, to wear the headphones, to select color-cued icons representing the different tasks or jobs to perform, and to select a color-cued hardware button to advance to the next step of the task analysis. In the second phase, students were required to turn-on the device and select a prerecorded icon, which caused a popped-up window to occur with a familiar picture plus auditory prompt, and to follow each instruction. Students also were required to press the hardware button to display the next direction. The prerecorded device instructed students to complete a two-step task familiar to students and normally associated with their morning classroom routine. Students were instructed to ‘‘close the door and hang up your coat,’’ or ‘‘sit down at the table and pick-up your pencil.’’ Each student was required to reach a criterion of 100% accuracy for two consecutive sessions. 1.7.2. Baseline Each session during baseline, as well as the succeeding phases, consisted of one opportunity for completion of all the steps in a task. During baseline, the students were presented with all of the materials required for the task. For each task, students were given a single verbal cue for task performance (e.g., ‘‘go gather the carts, prepare the broccoli, go clean the fitting room’’). No further assistance, instruction, or feedback was provided. 1.7.3. Handheld prompting procedures Students were provided with the handheld prompting system and headphones and instructed to turn on the device. After the device was activated, a pop-up window with an icon of the targeted task was displayed. After the student pressed the icon, a picture and auditory prompt of the first step of the task was displayed. Students then pressed the color-cued hardware button to advance to the next step of the task. As students followed the task sequences, a least-to-most prompt
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hierarchy was used until the student correctly performed the step. A 3-s interval between each prompt level was implemented. The least-to-most prompt hierarchy consisted of the following levels across instructional trials: (a) verbal prompt (e.g., ‘‘Did you hear and see what you are suppose to do?’’), (b) gesture (e.g., pointing to picture prompt on the handheld device), (c) gesture plus verbal explanation (e.g., pointing to the picture prompt and providing a verbal explanation), (d) modeling plus verbal explanation (e.g., pointing to the picture prompt, providing a verbal explanation, and demonstrating the correct response), and (e) physical assistance plus verbal explanation (e.g., holding the student’s wrist, pointing to the picture prompt, providing a verbal explanation, and physically assisting the student the correct response). Criterion for completion of this phase was 100% independent performance for three consecutive sessions. 1.7.4. Maintenance procedures Follow-up probes were collected 9 weeks after the student meet acquisition criterion on the fourth task. Follow-up probes occurred in the community setting where the student was initially trained. Follow-up probes were collected to determine if the initial instructional affected the student’s performance over time. 1.8. Reliability Interobserver reliability data and procedural reliability data were collected simultaneously by the primary investigator and the classroom teacher. Interobserver and procedural reliability data were collected during 33% of baseline and each concurrent phase. Observers independently and simultaneously recorded the number of steps the student performed independently or the required prompt and response time. Interobserver agreement was calculated by dividing the number of agreements of student responses by the number of agreements plus disagreements and multiplying by 100. Interobserver reliability ranged from 95 to 100%, with a mean of 98% agreement. The mean interobserver reliability agreement for each student across conditions was Jose, 100%; Curt, 96%; Nate, 100%, and Kim, 97%. Procedural integrity measures check the investigator’s performance by using the correct prompting hierarchy and response time. The classroom teacher was trained using an itemized checklist that listed the task-analyzed steps of each task and the level of prompt. The teacher was considered successfully trained after completing 100% of the checklist for three consecutive trials. The procedural agreement level was calculated by dividing the number of observed teacher behaviors by the number of planned teacher behaviors and multiplying by 100 (Billingsley, White, & Munson, 1980). Procedural reliability ranged from 96 to 100%, with a mean of 99%. The mean procedural reliability agreement for each student across conditions was: Jose, 99%; Curt, 100%; Nate, 96%; Kim 100% 2. Results The percentage of steps performed independently for students across increasing task complexity is presented in Figs. 1–4. Overall, students’ independent mean performance during baseline was 7% (range 2–17%) across tasks. All students increased independent task performance using the handheld prompting systems to a mean of 69% (range 62–74%) across tasks. Students also maintained all four skills 9 weeks later with 100% independence.
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Fig. 1. Jose’s percentage of steps performed independently across tasks.
2.1. Jose Fig. 1 displays the percentage of steps performed independently across tasks. The mean percentage of independent performance during baseline for gathering carts were 13%, stocking milk was 11%, vacuuming was 7%, and making sub-rolls was 2%. Using the handheld prompting device, the mean percentage of steps performed independently increased to 68% for gathering carts, 70% for stocking milk, 65% for vacuuming, and 70% for making sub-rolls. Jose also maintained 100% performance 9 weeks later. 2.2. Curt Fig. 2 displays the percentage of steps performed independently across tasks. The mean percentage of independent performance during baseline for gathering carts were 4%, stocking
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Fig. 2. Curt’s percentage of steps performed independently across tasks.
milk was 7%, vacuuming was 4%, and making sub-rolls was 3%. Using the handheld prompting device, the mean percentage of steps performed independently increased to 66% for gathering carts, 72% for stocking milk, 67% for vacuuming, and 76% for making sub-rolls. Curt also maintained 100% performance 9 weeks later. 2.3. Nate Fig. 3 displays the percentage of steps performed independently across tasks. The mean percentage of independent performance during baseline was 10% for self-prepping, 10% for preparing broccoli, 5% for skewering shrimp, and 8% for preparing tea. Using the handheld prompting device, the mean percentage of steps performed independently increased to 71% for
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Fig. 3. Nate’s percentage of steps performed independently across tasks.
self-prepping, 62% for preparing broccoli, 69% for skewering shrimp, and 64% for making tea. Nate also maintained 100% performance 9 weeks later.
2.4. Kim Fig. 4 displays the percentage of steps performed independently across tasks. The mean percentage of independent performance during baseline for straightening mushrooms was 17%, stocking bananas was 4%, stocking pineapples was 12%, and cleaning the fitting room was 5%. Using the handheld prompting device, the mean percentage of steps performed independently increased to 74% for straightening mushrooms, 66% for stocking bananas, 65% for stocking pineapples, and 85% for cleaning the fitting room. Kim also maintained 100% performance 9 weeks later.
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Fig. 4. Kim’s percentage of steps performed independently across tasks.
3. Discussion The purpose of this study was to demonstrate the use of a commercially produced handheld computer, as a prompting system, to facilitate generalization across increasingly complex tasks and to increase the probability of skill maintenance by adolescents with moderate intellectual disabilities. The results of this study parallel the findings of Wacker et al. (1985) and Briggs et al. (1990) research in which picture prompts and auditory prompts were used to increase generalization across dissimilar and increasing complex tasks without additional training. This study confirms previous research (Davies et al., 2002a, 2002b, 2003; Ferguson et al., 2005; Furniss et al., 2001; Riffel et al., 2005) that the use of handheld computers as a prompting system is a viable alternative prompting strategy to enhance independent performance for individuals with disabilities.
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This study extends the research literature of handheld computers by enabling students to use the handheld prompting system to learn to perform increasingly complex tasks without additional training in the operation of the prompting system. As no further training in the use of the handheld computer was needed during generalization conditions, it is noted that planned, programmed generalization occurred across tasks. Rather than relying on the ‘‘train and hope’’ strategy (Stokes & Baer, 1977), a specific plan for generalization of learning was incorporated into the instructional objective through use of the handheld prompting system. The second purpose of this study increased the probability of long-term maintenance of skills addressed by the use of the handheld prompting system. The learning of complex skills or chain tasks, the frequency of which only occurs sporadically in the natural environment, was maintained through a permanent prompt apparatus. People look up telephone numbers that we do not call frequently. People refer to recipes when preparing dishes that are only consumed occasionally. People follow instructions once a year to fill out income tax forms. The use of handheld computers as reminders when completing tasks is a natural and social valid, albeit technologically modern, means of maintaining performance. A third purpose was to use a commercially available handheld computer to enhance skill acquisition, generalization, and maintenance. The advantages of using commercially available products include lower costs, availability of operation manuals, and greater levels of technical supports. Moreover, when the universal design approach is applied, accessibility and usability of handheld computers increases. This promising technology, which promotes greater independence, can then be utilized by more individuals with disabilities. Since the professional literature recognizes that generalization and maintenance are difficult skills for students with moderate intellectual disabilities to learn, it is incumbent upon teachers and professionals to address these concerns in instructional program planning and teaching strategies. The use of a handheld computer prompting system is one way of enhancing this instructional component. With this methodology, teachers and professionals can increase the level of independence, self-sufficiency and the quality life of students with disabilities. Several limitations of this study may have affected the results and interpretations. First, task complexity was defined as increased motor responses. Tasks that also increased cognitive demands may produce differentiated outcomes. Second, the study was conducted with students who had extensive CBI experiences. Students with less extensive community experiences may require more intensive instruction to acquire, generalize, and maintain targeted skills. Third, all students demonstrated no resistant behaviors toward wearing the device and were extremely motivated using the handheld computer. Students who are less motivated or resistant to using the handheld computer may perform differently. Future research is needed to verify the results of this study and to investigate generalization across task complexity involving increase cognitive demands. Additionally, different community settings (e.g., restaurants, stores, and office buildings) and types of skills (e.g., domestic, leisure, and community) need to be investigated. Future research also should attempt to replicate these results across natural support instructors (e.g., job coach, co-worker, and parent), student characteristics, teacher to student ratio, frequency or training opportunities, and the inclusion of self-evaluation steps. References Alberto, P. A., Sharpton, W. R., Briggs, A., & Stright, M. H. (1986). Facilitating task acquisition through the use of a selfoperated auditory prompting system. The Association for Persons with Severe Handicaps, 11, 85–91.
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