O-060 Assessing Autism In Toddlers Born

Abstract

The Autism Diagnostic Observation Schedule (ADOS) is the only available semi-structured observational assessment of autism and has not been used extensively in preterm toddlers. We used a screening and diagnostic method to determine the diagnostic prevalence of autism and the characteristics of screen positive cases. <h3>Methods</h3> A 12-month birth-cohort of toddlers (2-and-4-years-old) born with a gestational age &lt;29-weeks were administered the Modified Checklist of Autism in Toddlers (M-CHAT)-and follow-up interview (FI™) screen, the ADOS and neurodevelopmental assessments (Bayley Scales of Infant and Toddler Development III-2-year-olds, Wechsler Preschool and Primary Scale of Intelligence-III and Adaptive Behaviour Assessment System-Second Edition-4-year-olds). The ADOS was conducted on toddlers with M-CHAT-FI™ positive screens. <h3>Results</h3> Complete data were available on 88% (169/192) of children. Thirteen-percent screened M-CHAT-FI™ positive. ADOS (DSM-IV-criteria) classified 1.8% with autistic disorder and none with ASD. Multivariate analysis showed that social emotional delay (p = &lt;0.001) was the only neurodevelopmental factor independently associated with M-CHAT-FI™ positive screens even after adjusting for psychosocial risk and child gender. All but one of the M-CHAT-FI™ positive screens scored some level of abnormality at the domain and item level on the ADOS testing, one third of these reached the Communication Total category cut off for ASD for the combined Communication and Social Interaction Total Score. Four children displayed comorbid atypical development (DQ/IQ &lt;-2SD). <h3>Conclusion</h3> The ADOS reports a lower incidence of autistic disorder in children born very preterm compared to studies using diagnostic interview based tools. The distinguishing features of the M-CHAT-FI™ positive cases suggest a sub-threshold communication dysfunction profile.