Mid-childhood outcomes of infant siblings at familial high-risk of autism spectrum disorder.

The high-risk groups were modest in size: 15 children with autism and 24 children without autism at age 7. The same clinicians took part in diagnosis at age 3 and age 7, so diagnostic stability findings were not fully independent. The sample's autism recurrence rate was higher than in large pooled high-risk sibling studies, which may limit generalisability to all high-risk siblings. One high-risk child could not do IQ testing, two high-risk children had insufficient language for the CELF, and four high-risk and 10 low-risk children did not complete the CELF because of time constraints. Proportions scoring above clinical cut-offs were not analysed statistically because few low-risk children were above threshold.

Do not assume high-risk siblings without autism are functioning typically across all areas. The 24 high-risk children without autism had typical-range IQ and no CELF language difference from low-risk controls, but they had lower adaptive behaviour and higher separation anxiety.