Trends in Domestic Intervention Research Using AAC for Individuals with Intellectual Disabilities

Objectives This study analyzes intervention research trends using AAC for individuals with intellectual disabilities to suggest educational practices and future research directions. Methods 17 domestic journal articles from 1999 to August 2024 were selected to analyze overall research trends (publication year, research participants, research design, dependent variables, validity, and fidelity), as well as characteristics of AAC-based interventions (intervention setting, tools, strategies and communication function of AAC). Results First, the analysis of overall trends showed that AAC interventions for individuals with intellectual disabilities started in 1999, with no published papers after 2022. Participants were mostly elementary school students, with pre-intervention communication levels falling below age 3 for expressive language and below age 5 for receptive language, except for adults. Research designs primarily included single subject, with multiple probe design across subjects being the most common. Communication was generally set as a dependent variable. Social validity and intervention fidelity were often omitted, while maintenance and generalization were measured in over 60% of studies. Second, detailed characteristics revealed that researchers often conducted interventions themselves, most commonly in classrooms and for less than 20 minutes. Non-electronic tools were used more than electronic ones, with MyTalkie program being the most actively used software. Various AAC interventions were applied along with script activities, with requesting/re-requesting being the most frequent communication function. Conclusions First, interventions should be applied to a wider range of ages, communication levels, and dependent variables. Enhancements in social validity, intervention fidelity, and generalization are needed to ensure research validity. In particular, training communication partners to ensure the generalization and continuity of AAC use for participants with intellectual disabilities is crucial. Second, the selection of AAC tools should consider participant preferences, and interventions should incorporate natural practice contexts to enhance the efficiency of learned AAC usage.