A Behavioral Intervention Package to Increase Vocalizations of Individuals with Autism during Speech-Generating Device Intervention
Gevarter, Cindy; Horan, Keri (2019). Journal of Behavioral Education, v28 n1 p141-167 Mar 2019. Retrieved from: https://eric.ed.gov/?id=EJ1207036
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examining6Students, gradePK
Practice Guide
Review Details
Reviewed: March 2026
- Practice Guide (findings for GoTalk speech generating device + prompting and reinforcement - Gevarter & Horan (2018))
- 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: 17%
Male: 83% -
Race Asian 17% Black 50% Other or unknown 33% -
Ethnicity Hispanic 33% Not Hispanic or Latino 67% -
Eligible for Free and Reduced Price Lunch Other or unknown 100%
Study Details
Setting
The study took place in a preschool classroom in a private preschool that served students with autism spectrum disorder or disabilities. The sessions took place in the preschool's speech therapy and technology rooms.
Study sample
Six preschool students with ASD participated in the study. Five of the students are males, three are African-American, one is Asian American, and two are Hispanic, with no race provided by the authors. The students ranged in age from 3.6 to 5.3 years old.
Intervention Group
This study examined the effect of a behavioral intervention package that used a speech-generating device (SGD) to promote the use of target vocalizations among students with ASD. Prior to the study, researchers worked with parents and teachers to identify a highly preferred item, such as candy or a toy, for each student, as well as items that were less preferred. In Phase I of the intervention, the preferred target item was placed behind the SGD, just beyond the child's reach. If the student vocalized the item (with or without selecting an image of it on the SGD) within six seconds of seeing the item, they were given access to the item. If the student vocalized correctly but did not correctly select the item on the SGD, the interventionist prompted the SGD response before providing the item. If the student selected the item on the SGD but did not vocalize it, or if they selected the incorrect item on the SGD, the interventionist prompted a correct SGD (if needed) and waited another six seconds. If the student vocalized the target word in that time period, they received the item; if they did not, they were giving a distractor trial (a clap) and a lower-preferred item. This review also included Phase II for three students (Daniel, Keith, and Stephen) who did not show increasing trends in response after Phase I. Phase II to Increase Rates, was the same as Phase I, except that after waiting 6 seconds for the first vocalization and an additional 6 seconds if there was a vocalization without SGD use, the interventionist vocalized the target item and waited an additional 6 seconds for the students' vocalization.
Comparison Group
There is no comparison group in single-case designs. During the baseline phase, the interventionist presented each student with a preferred item that was placed behind a speech-generating device (SGD), just beyond the child's reach. If the student independently selected an image of the item on the SGD within 6 seconds, the interventionist gave the student the item. If they did not input the correct response onto the SGD, the interventionist prompted the correct SGD response and then gave them the item. During this phase, the interventionist did not prompt students to vocalize the words or reward them if they did.
Support for implementation
The lead author, a board certified behavior analyst at the doctoral level, served as the interventionist for all participants.
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