Effects on Speech Development with Modifications to Picture Exchange Communication System
Emily N. White; Rachel R. Cagliani; Kelsie M. Tyson (2024). Focus on Autism and Other Developmental Disabilities, v39 n1 p14-23 2024. Retrieved from: https://eric.ed.gov/?id=EJ1412585
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examining3Students, gradePK
Practice Guide
Review Details
Reviewed: March 2026
- Practice Guide (findings for Picture Exchange Communication System (PECS) with delay + differential reinforcement + vocal model prompt - White et al. (2024))
- Single Case Design
- Meets WWC standards without reservations
This review may not reflect the full body of research evidence for this intervention.
Evidence Tier rating based solely on this study. This intervention may achieve a higher tier when combined with the full body of evidence.
Findings
To view more detailed information about the study findings from this review, please download findings data here.
Evidence Tier rating based solely on this study. This intervention may achieve a higher tier when combined with the full body of evidence.
Sample Characteristics
Characteristics of study sample as reported by study author.
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Female: 33%
Male: 67% -
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Race Black 100% -
Ethnicity Other or unknown 100% -
Eligible for Free and Reduced Price Lunch Other or unknown 100%
Study Details
Setting
The study took place in a self-contained preschool classroom for 3- and 4-year-old children with ASD and other developmental delays in a Title-I funded early intervention school in Southeastern United States. The regular classroom curriculum included goals pertaining to self-help skills, receptive and expressive communication, motor skills, and state-mandated PreK standards. Intervention sessions were conducted during meal times.
Study sample
Sample members were three Black preschool students with autism spectrum disorder. Two of the students were 4-year old males and one was a 4-year old female. All three students engaged in challenging and disruptive behaviors, such as dropping to the floor, throwing materials, and displaying aggression towards others. The students did not use speech to communicate and did not have prior experience with the augmentative and alternative communication (AAC). The classroom was staffed by graduate students and university special education and behavior analysis faculty, who served as "communication partners" to the students in the study.
Intervention Group
There were two intervention phases and this review focuses on the second intervention phase. The first intervention phase (PECS with delay + differential reinforcement) was reviewed separately. The intervention phases followed "Phase IV" of the Picture Exchange Communication System (PECS), which is a low-tech form of augmentative and alternative communication (AAC). In both intervention phases, Phase IV "delay to reinforcement and differential reinforcement" procedures were used to encourage vocalizations. After the child exchanged a sentence strip containing the phrase “I want” and a picture of the desired item, the communication partner read aloud "I want," and then waited 5 seconds before delivering the desired item. This delay was intended to create an opportunity for the child to spontaneously vocalize the name of the item. If a vocalization occurred during the delay, the child received a larger quantity of the item and verbal praise—a form of differential reinforcement. If vocalization did not occur during the delay, the communication partner then named and delivered the requested item to the participant, but without the enhanced reinforcement. The communication partner encouraged speech by delaying reinforcement, but always provided the requested item during exchanges whether the participant vocalized or not. In the second intervention phase (PECS with delay + differential reinforcement + vocal model prompt) which is the focus of this review, an additional intervention was introduced for children who did not independently vocalize 80 percent or higher during the delay + differential reinforcement phase. Following similar procedures to the other intervention phase, the communication partner said "I want" and then waited 5 seconds for the child to respond. If the child did not respond, the communication partner would deliver a vocal prompt ("I want [corresponding item name]") and waited for the child to repeat the prompt for 5 seconds. If the child repeated the prompt, they received the item and verbal praise. If they did not, the communication partner named the item again and gave the child a smaller portion of the edible item. Sessions were conducted during meal times for 20-min increments about 80 minutes apart. For the delay + vocal model prompt intervention, there were between 10 to 11 sessions. Each participant had an individualized three-ring binder with photographs of their preferred items, including edibles and toys, as well as a Velcro sentence strip.
Comparison Group
There is no comparison group in single-case designs. The baseline condition followed "Phase IV" of the Picture Exchange Communication System (PECS), without delay to reinforcement. Each student learned how to move two pictures onto a sentence strip and then give the strip to the communication partner. One picture stated, "I want," and the second picture included a visual of the requested item. During exchanges, the participants learned to point to each picture on the strip while the communication partner read the strip aloud. Baseline sessions continued until participants demonstrated mastery in moving both pictures to the strip and pointing to the pictures. Each participant had an individualized three-ring binder with photographs of their preferred items, including edibles and toys, as well as a Velcro sentence strip. For both contrasts, the same data points serve as the baseline phase in this review.
Support for implementation
Communication partners received training from the first study author, who had completed the Pyramid Educational Consultant Level 1 PECS training. The study team rehearsed research procedures and the first study author provided modeling and feedback.
Practice Guide
Review Details
Reviewed: March 2026
- Practice Guide (findings for Picture Exchange Communication System (PECS) with delay + differential reinforcement - White et al. (2024))
- Single Case Design
- Meets WWC standards without reservations
This review may not reflect the full body of research evidence for this intervention.
Evidence Tier rating based solely on this study. This intervention may achieve a higher tier when combined with the full body of evidence.
Findings
To view more detailed information about the study findings from this review, please download findings data here.
Evidence Tier rating based solely on this study. This intervention may achieve a higher tier when combined with the full body of evidence.
Sample Characteristics
Characteristics of study sample as reported by study author.
-
Female: 33%
Male: 67% -
- B
- A
- C
- D
- E
- F
- G
- I
- H
- J
- K
- L
- P
- M
- N
- O
- Q
- R
- S
- V
- U
- T
- W
- X
- Z
- Y
- a
- h
- i
- b
- d
- e
- f
- c
- g
- j
- k
- l
- m
- n
- o
- p
- q
- r
- s
- t
- u
- v
- x
- w
- y
South
-
Race Black 100% -
Ethnicity Other or unknown 100% -
Eligible for Free and Reduced Price Lunch Other or unknown 100%
Study Details
Setting
The study took place in a self-contained preschool classroom for 3- and 4-year-old children with ASD and other developmental delays in a Title-I funded early intervention school in Southeastern United States. The regular classroom curriculum included goals pertaining to self-help skills, receptive and expressive communication, motor skills, and state-mandated PreK standards. Intervention sessions were conducted during meal times.
Study sample
Sample members were three Black preschool students with autism spectrum disorder. Two of the students were 4-year old males and one was a 4-year old female. All three students engaged in challenging and disruptive behaviors, such as dropping to the floor, throwing materials, and displaying aggression towards others. The students did not use speech to communicate and did not have prior experience with the augmentative and alternative communication (AAC). The classroom was staffed by graduate students and university special education and behavior analysis faculty, who served as "communication partners" to the students in the study.
Intervention Group
The intervention condition followed "Phase IV" of the Picture Exchange Communication System (PECS), which is a low-tech form of augmentative and alternative communication (AAC). Phase IV "delay to reinforcement and differential reinforcement" procedures were used to encourage vocalizations, but this phase did not include additional prompting strategies like vocal models. In this phase, after the child exchanged a sentence strip containing the phrase “I want” and a picture of the desired item, the communication partner read aloud "I want," and then waited 5 seconds before delivering the desired item. This delay was intended to create an opportunity for the child to spontaneously vocalize the name of the item. If a vocalization occurred during the delay, the child received a larger quantity of the item and verbal praise—a form of differential reinforcement. If vocalization did not occur during the delay, the communication partner then named and delivered the requested item to the participant, but without the enhanced reinforcement. The communication partner encouraged speech by delaying reinforcement, but always provided the requested item during exchanges whether the participant vocalized or not. Sessions were conducted during meal times for 20-min increments about 80 minutes apart. There were between 7 to 10 sessions. Each participant had an individualized three-ring binder with photographs of their preferred items, including edibles and toys, as well as a Velcro sentence strip.
Comparison Group
There is no comparison group in single-case designs. The baseline condition followed "Phase IV" of the Picture Exchange Communication System (PECS), without delay to reinforcement. Each student learned how to move two pictures onto a sentence strip and then give the strip to the communication partner. One picture stated, "I want," and the second picture included a visual of the requested item. During exchanges, the participants learned to point to each picture on the strip while the communication partner read the strip aloud. Baseline sessions continued until participants demonstrated mastery in moving both pictures to the strip and pointing to the pictures. Each participant had an individualized three-ring binder with photographs of their preferred items, including edibles and toys, as well as a Velcro sentence strip.
Support for implementation
Communication partners received training from the first study author, who had completed the Pyramid Educational Consultant Level 1 PECS training. The study team rehearsed research procedures and the first study author provided modeling and feedback.
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