Augmentative and Alternative Communication for Children with Intellectual and Developmental Disability: A Mega-Review of the Literature

Abstract

Establishing evidence-and research-based practices relies upon research synthesis of individual studies in reviews and meta analyses. Further summarizing scientific evidence about a specific topic by synthesizing reviews is an area of need to determine practices that have a strong evidence base and to identify areas of methodological weakness and gaps in the literature. A mega-review of literature reviews, systematic reviews, and meta-analyses on interventions using aided augmentative and alternative communication (AAC) interventions for children with intellectual and developmental disabilities from 2000 to mid-2020 was conducted. Participant and interventionist demographics, interventions, settings, outcomes, and recommendations of each review were reported and summarized. A MeaSurement Tool to Assess systematic Reviews Revised (AMSTAR 2; Shea et al., 2017) was used to examine the methodological rigor of 84 included reviews. Over the past 20 years, published reviews have increased slightly in methodological rigor but demonstrate a number of methodological weaknesses that detract from the strength of evidence for AAC interventions with this population. Suggestions for improving the methodological rigor of literature reviews and areas for future research specific to AAC interventions are discussed.

Parents’ Perceptions and Experiences with Their Children’s Use of Augmentative/Alternative Communication: A Systematic Review and Qualitative Meta-Synthesis

“…The ten items on the CASP checklist are classified in a numerical outcome (No = 0, Cannot Tell = 0.5 (when the provided information is insufficient or not clear), Yes = 1), with a maximum total score of 10. Following Butler et al [17], we categorized the total CASP score for all studies in three categories (high, moderate, low) and the methodological quality was high (>8-10), moderate (6)(7)(8), or low (≤5). The third and last authors completed the CASP analysis independently and then discussed any disagreements before coming to an agreed consensus (kappa = 0.88).…”

“…Considering the large number definitions of AAC offered in the literature, we adopted the definition by Crowe et al [8], for a study to be included in the current review. Therefore, AAC comprises unaided systems such as manual signs and gestures as well as aided systems such as the Picture Exchange Communication System and speech generating devices (SGD).…”

“…Low-technology systems or devices encompass communication books or boards (non-battery powered), written words on paper, line drawings, symbols on a ring or in a notebook, photographs, and pictograms such as the Picture Exchange Communication System (PECS; Bondy and Frost [6]). High-technology systems include speech generating devices (SGD) or voice output communication aids (VOCAs), and software on tablets, computers, mobiles, iPads, and/or apps used as communication aid [7,8]. Moreover, aided AAC systems are most often selected for individuals with complex communication needs and can contribute to more positive outcomes for this population [9].…”

“…Similarly, White et al [14] evaluated the effects of AAC on speech development in children with ASD, highlighting that it is still unclear if the addition of AAC will benefit a participant's speech production. More recently, a mega-review summarized published peer-reviewed literature reviews about aided AAC interventions that included children with developmental disabilities [8]. The need for increasing generalization and maintenance programming and ensuring that lasting and social important behaviors occur with the use of AAC was highlighted.…”

Commentary and Clinical Implications of “State of the Evidence Traffic Lights 2019: Systematic Review of Interventions for Preventing and Treating Children with Cerebral Palsy”

“…AAC is considered a yellow light intervention with a small body of very low-quality evidence supporting its use in children with cerebral palsy to improve their communication, supplement verbal speech and increase peer interactions. However, a more robust evidence exists outside the cerebral palsy population [46], supporting targeting outcomes including (i) development of functional communication skills [47], (ii) improved expressive and receptive language and social skills [48], (iii) verbal speech development [49][50][51], and (iv) quality of life and independence [52].…”