Effectiveness of a Multicomponent Reading Intervention: A Longitudinal Study of Individuals with Autism and Intellectual Disabilities Using Augmentative and Alternative Communication

Abstract Background Research indicates a lack of competence, expectations, and evidence-based reading programs tailored for individuals with disabilities who utilize augmentative and alternative communication. This study investigated the effects of a longitudinal and multicomponent reading intervention on 40 students aged 6 to 14 with Autism Spectrum Disorder and/or Intellectual Disability requiring augmentative and alternative communication (AAC). Methods The reading intervention utilized multiple single-case designs with multiple randomized baselines to investigate the effect of an AAC-adapted reading material concerning phonological awareness, letter sound correspondence, decoding, shared reading, and sight words, and its effectiveness was measured using a generalized estimating equation. Results Evidence of the effects of the intervention phase compared to the control phase is lacking; however, within the intervention phase, scores showed an increase over time. Statistical analysis identified significant results only within sound blending. Moreover, an adapted standardized reading test was administered, confirming that 13 students developed phonological reading skills. Almost half of the participants also attained phonological awareness. Conclusions Most students demonstrated an increase in their early reading competence, irrespective of their speech abilities, age, and severity of diagnosis. Due to the heterogeneity of the sample, it is crucial to examine each student’s outcomes. The present study contributes to the debate and the limited research base related to comprehensive and longitudinal reading instructions for students with autism and/or intellectual disabilities who require augmentative and alternative communication. Moreover, it provides important information to build upon, confirming previous findings that students many have low expectations of can achieve early reading skills. This study is registered with ClinicalTrials.gov (NCT05709405, registered on January 23, 2023). As the study involved educational, not health care, interventions, further registration was deemed unnecessary.