On the Spectrum

White matter microstructure in children with autistic traits
remained after adjustment for a set of standard confounders, we additionally performed a
sensitivity analysis adjusting for IQ and attention problems.
Additionally, we evaluated whether any associations with white matter microstructure
remained after excluding children with a confirmed diagnosis of ASD. Lastly, any differences
identified using the trait approach were also evaluated in the 19 children in our sample with
clinically confirmed ASD, compared to a group of age, sex and IQ-matched controls. For this
analysis, group status (ASD/control) was used as a predictor in linear regression models.
RESULTS
Sample characteristics
Sample characteristics are presented in Table 1.
Table 1. Participant characteristics (n=604)
Child characteristics
n
Gender (% boy) 604 53.0
Ethnicity 604
Dutch 65.2
Other Western 9.3
Non-Western 25.5
Social Responsiveness Scale
Weighted total score 604 0.27 (0.29)
Age at Social Responsiveness Scale (years) 604 6.17 (0.44)
Age at MRI (years) 604 8.02 (1.03)
Non-verbal IQ 554 103.4 (14.1)
Maternal characteristics
Education level (%) 591
High 57.3
Medium 29.5
Low 11.1
Alcohol in pregnancy (%) 563
Never 32.7
Until pregnancy was known 14.9
Continued occasionally 40.7
Continued frequently 11.7
4
Smoking in pregnancy (%) 583
Never 77.4
Until pregnancy was known 6.3
Continued 16.3
Note. Values are mean and SD unless otherwise indicated.
85