Augmentative and alternative communication (AAC) interventions that promote commenting: a systematic review

Augmentative and alternative communication (AAC) can be used effectively by persons with speech or speech-related disabilities to accomplish a variety of communicative functions. However, the majority of AAC interventions reported in the literature focused on requesting. While it is important to initially teach requesting skills, commenting should not be neglected. As AAC emerges, commenting is essential for social engagement, social closeness and information transfer. The purpose of this systematic review (INPLASY protocol 3160) was to describe and critically appraise the existing research on AAC interventions for commenting. A systematic search and application of inclusion criteria yielded 14 single case design studies that examined the effect of an AAC intervention on commenting of children with communication disabilities. A quality appraisal indicated that the rigor of most studies was acceptable. However, there are areas in which research can be improved, especially around the number of points per phase, blinding of personnel, and clear reporting of procedures. Interventions fell into three types of teaching procedures, including prompt hierarchies, aided modeling and direct prompting. Likewise, three teaching contexts (i.e., book reading, play/toys/preferred activities, intensive teaching) and four types of commenting behaviors (i.e., one-symbol utterances, two-symbol utterances, sentences frames and grammatically correct utterances) were identified. Findings suggest the strongest evidence exists to support the use of least-to-most prompt hierarchies that include aided modeling in the context of book reading. However, there are too few studies to recommend their use with certainty.