15551
Gesture Production As a Predictor of Outcomes for Children with Autism in Early Intervention
Predictors of treatment outcomes for children with autism spectrum disorder (ASD) have been extensively studied, but less is known about individual differences that may explain variation in response to early intervention. Given that specific gestures, such as pointing for joint attention, presage subsequent language acquisition in children with and without ASD, the present study characterized differences in gesture and tested whether these aid in predicting outcomes in ASD.
Objectives:
This study used a multi-method approach for measuring gesture production as a predictor of treatment outcomes for children with ASD enrolled in early intensive behavioral intervention. This study also derived latent constructs to represent gesture production and treatment outcomes.
Methods:
Participants included 71 children with ASD who received early, intensive behavioral intervention for a period of two years (mean age at intake=3.28 years; 60 males) as part of a study that evaluated predictors of intervention response. Gesture production was represented with scales from the MacArthur Communicative Development Inventory (Fenson et al., 1993), the Early Social Communication Scale (Mundy & Hogan, 1986), and items from the Autism Diagnostic Interview–Revised (Lord et al., 1994). A coding system was also developed to capture the diversity of gestures children produced with their gestures during the Autism Diagnostic Observation Schedule. Treatment outcomes were represented with the Mullen Scales of Early Learning (Mullen, 1995), Vineland Adaptive Behavior Scales (Sparrow et al., 1984), and the Autism Diagnostic Observation Schedule (Lord et al., 2000). Structural equation models tested how gesture at intake predicted variability in outcome change at both follow-up assessments.
Results:
A latent construct representing gesture was successfully obtained χ2(1)=.21, p=.65, CFI=.99, RMSEA=.01, and used to evaluate gesture’s relationship with treatment outcomes. Treatment outcomes were best represented as a latent construct with scores from the Mullen and Vineland scales. A change regression model (McArdle, 2009) indicated that gesture and outcome significantly co-varied at the intake assessment such that higher scores on the outcome construct were associated with higher levels of gesture, r=.73, p<.001. Moreover, gesture significantly predicted variability in change such that participants with higher intake levels of gesture showed greater amounts of improvement on the outcome construct at both the Year 1 (β=.50, p=.002) and Year 2 (β=.42, p=.01) assessments. Gesture production remained a significant positive predictor of the variability in change at each assessment (Year 1: β=.41, p=.009; Year 2: β=.36, p=.03) when caregiver report of speech production was included as a concurrent predictor.
Conclusions:
This study showed that initial differences in gesture production could be used to predict variability in treatment outcome. Participants who began treatment with higher gesture production showed greater gains in outcome, and this effect remained even after controlling for concurrent speech. Given that early intervention strives to improve the functioning of children with ASD during a period marked by greater plasticity and a heightened possibility for accelerating the rate of change (Warren et al., 2011), these results suggest that higher levels of gesture may magnify the benefits of early intervention for children with ASD.