Abstract
PURPOSE: The current study compared the spontaneous expressive language of children with autism spectrum disorder (ASD) across multiple language sampling contexts: the Autism Diagnostic Observation Schedule (ADOS; Lord, Rutter, DiLavore, & Risi, 1999) and play with an examiner or parent. METHOD: Participants were children with ASD (n = 63; 55 boys) with a mean age of 45 months (SD = 3.94, range = 37-53). The number of utterances produced; percentage of intelligible utterances; number of different words; mean length of utterance; and the number of requests, comments, and instances of turn-taking were calculated for the ADOS, examiner-child play, and parent-child play. Children were categorized into Tager-Flusberg et al.'s (2009) developmental language phases for each context. RESULTS: Effects of sampling context were identified for all variables examined. The ADOS resulted in fewer utterances and lower structural and pragmatic language performance than examiner-child play and/or parent-child play. Categorization of children into language phases differed across contexts. CONCLUSIONS: Use of the ADOS as a language sampling context may lead to underestimating the abilities of young children with ASD relative to play with an examiner or parent. Researchers and clinicians should be aware of context effects, particularly for assessments designed to observe autism symptoms.