2016
Gatlinburg Conference Poster
PS‐19 Title: Skill Profiles and Communication Growth in Minimally Verbal Children with ASD Authors: Charlotte DiStefano, Wendy Shih, Ann Kaiser, Rebecca Landa, Pamela Mathy, Connie Kasari Introduction: Approximately 30% of children with autism spectrum disorders (ASD) are minimally verbal past age 5. Despite limited expressive language, these children demonstrate considerable variability in their other abilities, such as non‐verbal cognition and receptive language. More research is needed to characterize these abilities, and to understand how abilities across domains are related to spoken language outcomes in children with ASD. Objectives: This study seeks to 1) find common skill profiles in a sample of minimally verbal children with ASD, and 2) determine how baseline ability profiles are related to outcomes in a spoken language intervention. Methods: Participants included 50 minimally verbal children with ASD from a 6‐month intervention study, employing a blended intervention ‐ Joint Attention, Symbolic Play, Engagement and Regulation (JASPER) and Enhanced Milieu Teaching (EMT). Participants were randomized to Speech (spoken language only) or AAC (spoken language plus augmentative/alternative communication device) versions of the intervention (Kasari et al., 2014). K‐means analysis was used to identify skill clusters based on baseline assessment results across domains (ASD severity, repetitive behaviors, NVIQ and language). Linear mixed modeling was used to evaluate trajectories in spoken language growth based on skill clusters and treatment groups. Post‐hoc contrasts were used to identify pair‐wise differences. Results: 4 clusters were identified. Cluster 1 (N=6) had the most impaired abilities across domains. Cluster 2 (N=5) had mid‐
range abilities across domains, but the highest rate of communicative utterances. Cluster 3 (N=27) mixed abilities across other domains. Cluster 4 (N=12) had a moderate rate of communicative utterances and the highest abilities across other domains. To examine spoken language outcomes, clusters were divided based on treatment assignment. Cluster 2 was removed from further analysis due to its small size, resulting in 6 groups (3 clusters by 2 treatment conditions). The mixed model indicated that growth in communicative utterances over the course of the study varied across groups (X2=27.2, p=.002). Post‐hoc analyses revealed that, in phase 1 of intervention (1st 3 months), participants in cluster 4 who were randomized to the AAC condition had significantly higher communication growth than participants in clusters 3 and 4 who were randomized to spoken language only (p=.005, p=.01). In phase two of intervention (2nd 3 months), cluster 4‐AAC participants showed a negative slope in communicative utterances, which was significantly different than the positive slopes exhibited by participants in all other cluster by treatment groups (p‐value range: .048‐.003). Discussion: In this sample of minimally verbal children with ASD, distinct skill profiles were identified. Patterns of spoken language growth were found to vary across these clusters. In particular, participants who were randomized to the AAC condition, and demonstrated the highest baseline cognitive abilities, displayed initially rapid growth in spoken language, followed by a decrease in spoken language in the latter half of the study. Although the AAC condition was associated with better spoken language outcomes overall, the results of this analysis indicate that additional strategies may be needed to sustain spoken language growth in this subgroup of participants. Further research is needed to determine whether similar skill profiles can be found in additional samples of minimally verbal children with ASD and how these skill profiles relate to longitudinal outcomes. References/Citations:  Kasari, C., Kaiser, A., Goods, K., Neitfeld, J., Mathy, P., Landa, R., Murphy, S. & Almirall, D. (2014). Communication interventions for minimally verbal children with autism: A sequential multiple assignment randomized trial. Journal of the American Academy of Child and Adolscent Psychiatry, 53(6), 635‐646.