Longitudinal Effects of Adaptive Interventions With a Speech-Generating Device in Minimally Verbal Children With ASD

Abstract

There are limited data on the effects of adaptive social communication interventions with a speech-generating device in autism. This study is the first to compare growth in communications outcomes among three adaptive interventions in school-age children with autism spectrum disorder (ASD) who are minimally verbal. Sixty-one children, ages 5-8 years, participated in a sequential, multiple-assignment randomized trial (SMART). All children received a developmental behavioral communication intervention: joint attention, symbolic play, engagement and regulation (JASP) with enhanced milieu teaching (EMT). The SMART included three 2-stage, 24-week adaptive interventions with different provisions of a speech-generating device (SGD) in the context of JASP+EMT. The first adaptive intervention, with no SGD, initially assigned JASP+EMT alone, then intensified JASP+EMT for slow responders. In the second adaptive intervention, slow responders to JASP+EMT were assigned JASP+EMT+SGD. The third adaptive intervention initially assigned JASP+EMT+SGD; then intensified JASP+EMT+SGD for slow responders. Analyses examined between-group differences in change in outcomes from baseline to Week 36. Verbal outcomes included spontaneous communicative utterances and novel words. Nonlinguistic communication outcomes included initiating joint attention and behavior regulation, and play. The adaptive intervention beginning with JASP+EMT+SGD was estimated as superior. There were significant (p < .05) between-group differences in change in spontaneous communicative utterances and initiating joint attention. School-age children with ASD who are minimally verbal make significant gains in communication outcomes with an adaptive intervention beginning with JASP+EMT+SGD. Future research should explore mediators and moderators of the adaptive intervention effects and second-stage intervention options that further capitalize on early gains in treatment.

Trial registration: ClinicalTrials.gov NCT01013545.

Figure 1

Schematic of the sequential multiple assignment randomized trial (SMART) design, with sample sizes at each stage. Notes. See manuscript text for definition of Responder versus Slow Responder. Abbreviations: JASP—Joint attention, social engagement, and play; EMT—Enhanced milieu training; SGD—Speech generating device.

Figure 2

Estimated average trajectories under each of the embedded adaptive interventions. Notes. See Table 1 and Figure 1 to understand how the three adaptive interventions are defined. Trajectories are shown for the two significant outcomes: (a) total spontaneous communicative utterances (TSCU) and (b) initiating joint attention (IJA). Abbreviations: SGD—Speech generating device.