Meta-Analyses of Variables Related to Instruction in Augmentative and Alternative Communication Implementation

Abstract

Purpose: The purpose of this project was to conduct a comprehensive meta-analysis to determine whether augmentative and alternative communication (AAC) is associated with improved outcomes (e.g., behavior and communication) for individuals with autism and/or intellectual/developmental disabilities (IDD). Although AAC is widely used in educational settings, it is unclear for whom and under what conditions it is most effective. This project aimed to address this gap by conducting a systematic review and meta-analysis to explore relationships between AAC and education-related outcomes for individuals with IDD. The project evaluated the quality of reporting of the primary literature base. The project also examined whether effects of AAC interventions differ based on participant characteristics, including diagnosis, age, number and type of communication modes prior to study implementation, participants’ productive repertoires, and imitation skills prior to intervention. The project examined if effects differ based on the instructional contexts, including setting (e.g., home, classroom, clinic), type of instructional features implemented (e.g., reinforcement, modeling, prompts, prompt fading), and behavioral intervention strategies (e.g., child or interventionist initiated, dispersed versus massed teaching opportunities, contrived versus embedded activity contexts). The project also evaluated whether effects differed based on intervention targets and communication modes implemented, including number and type of communication modes employed, communicative functions taught, and verbal/vocal versus non-verbal/vocal outcomes selected for treatment. Ultimately, the results provide important information to researchers on the need for the development of AAC interventions and to practitioners and caregivers on how best to individualize AAC interventions.