We examined the home-based concerns reported by mothers of infant siblings of children with autism across the first year of life. At all three ages measured, mothers of high-risk infants were significantly more likely than mothers of low-risk infants to report language, social communication, and restricted and repetitive behavior concerns but were…

To identify possible early signs of autism spectrum disorder (ASD) within the Danish National Birth Cohort, we studied prospectively collected interviews from 76,441 mothers about their children's development and behaviour at 6 and 18 months. In Danish national registries, 720 children with ASD and 231 children with intellectual disability (ID)…

A parent-report instrument, the First Year Inventory (FYI), was developed to assess behaviors in 12-month-old infants that suggest risk for an eventual diagnosis of autism. The target behaviors were identified from retrospective and prospective studies. FYIs were mailed to 5,941 families and 25% (N = 1,496) were returned, with higher return rates…