Predictors of Language Development in Young Children with Autism Spectrum Disorder: A Longitudinal Study

Background: Previous studies have shown that early language ability is related to long-term outcomes and adaptive function in children with autism spectrum disorder (ASD). It is an important issue to explore predictors of language development in young children with ASD. Joint attention and imitation were supported that they could enhance language development in young children with ASD. However, there were few longitudinal studies to examine that both joint attention and imitation contribute to language development in young children with ASD under 36-months-old.

Objectives: The purpose of this longitudinal study was to examine that joint attention and imitation predict language development in young children with ASD less than 36 months.

Methods: The participants were 74 young children with ASD aged 17-35 months (M = 24.2, SD = 4.4) at initial assessment who were followed up 18 months after their initial assessment. The Screening Tool for Autism in Two-Year-Olds, Taiwan version (T-STAT; Chiang et al., 2013) was modified for measuring joint attention and imitation, including initiating joint attention, responding joint attention, object imitation and manual imitation. In addition, Mullen Scales of Early Learning (MSEL; Mullen, 1995) was used for assessing language abilities, including receptive language, expressive language and overall language. Joint attention and imitation were assessed at initial assessment and language abilities were assessed at two time points.

Results: Language abilities at 24 months, all of receptive language, expressive language and overall language were concurrent correlated with joint attention and imitation. The significant concurrent predictors of receptive language and overall language were responding joint attention and manual imitation. In addition, the significant concurrent predictor of expressive language was manual imitation. Language abilities at 42 months, all of receptive language, expressive language and overall language were longitudinal correlated with responding joint attention and imitation. The significant longitudinal predictors of receptive language and overall language were responding joint attention and manual imitation. In addition, the significant longitudinal predictor of expressive language was manual imitation.

Conclusions: Results of this longitudinal study showed that responding joint attention and imitation were concurrent and longitudinal correlated with language abilities in young children with ASD. However, initiating joint attention was only concurrent correlated with language abilities in young children with ASD. The results showed that manual imitation was the stronger predictors for receptive language, expressive language and overall language at 24 months and at 42 months in young children with