Early Gesture as a Predictor of Later Language Outcome for Young Children with Autism Spectrum Disorder (ASD): a Systematic Literature Review

Purpose of Review This systematic review aimed to locate through the literature early gesture predictors for later language development in children with autism spectrum disorder (ASD). Electronic databases were systematically searched using "gesture," "language," and "ASD," along with their synonyms based on specific criteria, including baseline gesture and follow-up language measures, as well as use of statistics for calculating longitudinal predictability as a prerequisite. Recent Findings Thirteen studies met all the eligibility criteria. Results showed that children with ASD, after the age of 12 months, presented with less and different gestures, and this early gesture level was found to usually predict their later language outcome. More specifically, the total amount of gestures or inventory of gestures mainly predicted receptive language development, while joint attention, deictic, and right-handed deictic gestures mainly predicted expressive language development. Only two studies did not find gesture as a predictor of later language. Variability between the studies concerning the age of the sample at baseline, duration of follow-up, and the different types of gestures, as well as the different types of tools used to quantify gesture and language, resulted in some inconsistent results that were discussed. This review helped align existing studies to shed light on the need for further, low bias studies to establish whether results can be replicated, so that more robust conclusions on using gesture as an early screening tool for language delay in toddlers with ASD can be drawn. Suggestions for future research were made.