Extended Data Table 1 Subject demographics (including tests for group differences)
From: Early brain development in infants at high risk for autism spectrum disorder
- No significant group differences (between HR-ASD, HR-neg and LR) were observed in race/ethnicity, family income, maternal age at birth, infant birth weight, gestational age at birth, or age at visit. As expected, on the basis of the disproportionately higher rates of ASD in males, the HR-ASD group contained significantly more males than the LR group
. We also observed that the LR group had higher maternal education compared to the other two groups 
. As expected, on the basis of the association between intellectual disability and ASD, the HR-ASD group had significantly lower Mullen and Vineland scores at 24 months than the other two groups. Mullen ELC, Early Learning Composite standard score; Vineland ABC, Vineland Adaptive Behaviour Composite standard score; SD, standard deviation.
. We also observed that the LR group had higher maternal education compared to the other two groups 
. As expected, on the basis of the association between intellectual disability and ASD, the HR-ASD group had significantly lower Mullen and Vineland scores at 24 months than the other two groups. Mullen ELC, Early Learning Composite standard score; Vineland ABC, Vineland Adaptive Behaviour Composite standard score; SD, standard deviation.