IQ, parent- and self-reports of child anxiety and salivary cortisol in a sample of children with autism spectrum disorder

This study examined the relation between IQ, parent-reported child anxiety, and salivary cortisol levels in youth with autism spectrum disorder (ASD) with a wide range of intellectual abilities using a prospective design. Results showed that IQ at time 1 (T1) positively predicted parentreports of child anxiety at time 2 (T2); however, IQ at T1 negatively predicted cortisol levels from saliva samples taken at a research laboratory at T2. Parent reports of child anxiety at T1 and T2 were not associated with cortisol levels at T2. Implications for the assessment of anxiety in youth with ASD are discussed.