Empowering Partners: Cascading Coaching to Enhance Caregiver Use of AAC-Embedded NDBI Strategies

Abstract

Aim: Naturalistic developmental behavioral interventions (NDBIs) target skills across learning domains by emphasizing developmental progression within naturally occurring routines (Shreibman et al., 2015). Although NDBIs often facilitate language growth in young autistic children, they rarely incorporate alternate communication modalities for children without functional speech (Kasari et al., 2014). Pope et al. (2025) found that integrating augmentative and alternative communication (AAC) into NDBIs improves outcomes for non‑speaking autistic children; however, none of the reviewed studies involved caregivers as the communication partner. Caregiver involvement is essential for young autistic learners, yet caregivers frequently report insufficient training as a barrier to AAC implementation (Kim & Soto, 2024). This study examined the feasibility of coaching caregivers to use adapted NDBI strategies that incorporate their child’s AAC system. Research questions included: (1) What impact do caregiver‑implemented NDBI‑AAC strategies have on autistic children’s communication outcomes? (2) How effectively do caregivers implement NDBI strategies that incorporate AAC support for non‑speaking autistic children?

Method: A multiple‑probe across communication partner design was used to evaluate implementation of adapted NDBI‑AAC strategies. A Cascading Coaching model was employed: the experienced speech-language pathologist (SLP)/researcher coached a SLP graduate student clinician, who then coached the caregiver. Participants were three triads consisting of a graduate student clinician, a caregiver, and an autistic preschooler. Graduate student clinicians were recruited based on interest in pediatric intervention and completion of AAC and Autism coursework or related clinical experience. Caregivers and children were recruited through convenience and purposeful sampling. Children were required to be 2.5–6 years old, have a diagnosis or indicators of ASD, demonstrate symbolic communication (Communication Matrix Levels 5–6), and benefit from AAC.

The study occurred during a four‑week summer camp (3 days/week). Child participants engaged in two daily 15‑ to 30‑minute sessions—one with the clinician and one with the caregiver. Each session included a 15‑minute play routine aligned with NDBI principles. Coaching sessions were extended to 30 minutes and included planning, visual supports, in‑session modeling, and performance‑based feedback. Communication temptations (e.g., delayed assistance, interrupted routines) were paired with individualized communication functions (e.g., requesting help, commenting) selected through intake, parent report, and baseline assessment. Fidelity was measured using a pre‑defined checklist and the NDBI Fidelity Rating Scale (NDBI‑FI; Frost et al., 2020). Social validity was assessed through semi‑structured caregiver and clinician interviews.

Results: Preliminary analyses indicate positive effects of caregiver coaching on communication. All children demonstrated increases across multiple communicative functions (e.g., requesting items out of sight, requesting help, commenting) with both communication partners. Adult behavior measured by the NDBI‑FI showed increased strategy use—including following the child’s lead, positioning at the child’s level, using communication temptations, and responding to communication attempts—with average implementation fidelity of 92.5%. Although clinicians showed slightly higher fidelity than caregivers, both exceeded baseline levels.

Conclusion: Findings suggest that caregiver‑implemented NDBI‑AAC strategies taught through cascading coaching are feasible, effective, and supportive of communication growth for non‑speaking autistic children who use AAC. These results reinforce the study’s aim by demonstrating that integrating AAC into NDBIs—and equipping caregivers to deliver these strategies—can meaningfully enhance communication outcomes within naturalistic routines.

Citations:

Frost, K. M., Brian, J., Gengoux, G. W., Hardan, A., Rieth, S. R., Stahmer, A., & Ingersoll, B. (2020). Identifying and measuring the common elements of naturalistic developmental behavioral interventions for autism spectrum disorder: Development of the NDBI-Fi. Autism, 24(8), 2285–2297. https://doi.org/10.1177/1362361320944011

Kasari, C., Kaiser, A., Goods, K., Nietfeld, J., Mathy, P., Landa, R., & Almirall, D. (2014). Communication interventions for minimally verbal children with autism: A sequential multiple assignment randomized trial. Journal of the American Academy of Child & Adolescent Psychiatry, 53(6), 635–646. https://doi.org/10.1016/j. Jaac.2014.01.019

Kim, J., & Soto, G. (2024) A Comprehensive Scoping Review of Caregivers’ Experiences with Augmentative and Alternative Communication and Their Collaboration With School Professionals. Language, Speech, and Hearing Services in Schools, 55, 607-627, https://doi.org/10.1044/2024_LSHSS-23-00117

Pope, L., Light, J., & Laubscher, E. (2025) The Effect of Naturalistic Developmental Behavioral Interventions and Aided AAC on the Language Development of Children on the Autism Spectrum with Minimal Speech: A Systematic Review and Meta-analysis. Journal of Autism and Developmental Disorders, 55, 3078-3099. https://doi.org/10.1007/s10803-024-06382-7

Schreibman, L., Dawson, G., Stahmer, A. C., Landa, R., Rogers, S. J., McGee, G. G., & Halladay, A. (2015). Naturalistic developmental behavioral interventions: Empirically validated treatments for autism spectrum disorder. Journal of Autism and Developmental Disorders, 45(8), 2411–2428. https://doi.org/10.1007/ s10803-015-2407-8