In order to shed more light on why referred girls are less likely to be diagnosed with autism spectrum disorder than boys, this study examined whether behavioral characteristics influence the probability of an autism spectrum disorder diagnosis differently in girls versus boys derived from a multicenter sample of consecutively referred children aged 2.5-10 years. Based on information from the short version of the Developmental, Dimensional and Diagnostic Interview and the Autism Diagnostic Observation Schedule, 130 children (106 boys and 24 girls) received a diagnosis of autism spectrum disorder according to Diagnostic and Statistical Manual of Mental Disorders (4th ed., text rev.) criteria and 101 children (61 boys and 40 girls) did not. Higher overall levels of parent-reported repetitive and restricted behavior symptoms were less predictive of an autism spectrum disorder diagnosis in girls than in boys (odds ratio interaction = 0.41, 95% confidence interval = 0.18-0.92, p = 0.03). In contrast, higher overall levels of parent-reported emotional and behavioral problems increased the probability of an autism spectrum disorder diagnosis more in girls than in boys (odds ratio interaction = 2.44, 95% confidence interval = 1.13-5.29, p = 0.02). No differences were found between girls and boys in the prediction of an autism spectrum disorder diagnosis by overall autistic impairment, sensory symptoms, and cognitive functioning. These findings provide insight into possible explanations for the assumed underidentification of autism spectrum disorder in girls in the clinic.

The Developmental Diagnostic Dimensional Interview-short version (3Di-sv) provides a brief standardized parental interview for diagnosing autism spectrum disorder (ASD). This study explored its validity, and compatibility with DSM-5 ASD. 3Di-sv classifications showed good sensitivity but low specificity when compared to ADOS-2-confirmed clinical diagnosis. Confirmatory factor analyses found a better fit against a DSM-5 model than a DSM-IV-TR model of ASD. Exploration of the content validity of the 3Di-sv for the DSM-5 revealed some construct underrepresentation, therefore we obtained data from a panel of 3Di-trained clinicians from ASD-specialized centers to recommend items to fill these gaps. Taken together, the 3Di-sv provides a solid basis to create a similar instrument suitable for DSM-5. Concrete recommendations are provided to improve DSM-5 compatibility.Electronic supplementary materialThe online version of this article (doi:10.1007/s10803-016-2713-9) contains supplementary material, which is available to authorized users.

This paper provides an overview of the design and cohort characteristics of the Social Spectrum Study: a clinical cohort study that used a two-phase sampling design to identify children at risk for ASD. After screening 1281 children aged 2.5–10 years who had been consecutively referred to one of six mental health services in the Netherlands, children who screened positive for ASD (n = 428) and a random selection of screen negatives (n = 240) were invited to participate in diagnostic assessments and questionnaires regarding the child, family and society. A 1-year follow-up was also conducted. Results from this study may contribute to knowledge of the identification and characterization of children with ASD, family processes, and the impact of ASD on the family and society.