Demographic Characteristics.

Mann-Whitney U test, SCQ: Social Communication Questionnaire, FSIQ: IQ total, VIQ: verbal IQ, PIQ: performance IQ, A: ADOS-A (Autism Diagnostic Observation Schedule-A): communication score, B: ADOS-B: social score, the threshold scores for a diagnosis of autism on the ADOS are 3 and 6 for communication and social symptoms, respectively. Threshold scores for a less severe diagnosis of ASD on the ADOS are 2 and 4 for communication and social symptoms, respectively. Mo: months, CARS: Child Autism Rating Scale, ASD: autism spectrum disorders, HC: healthy comparison subjects.