To fulfill the criteria for autism spectrum disorder (ASD), symptoms must be present across domains and contexts. We assessed preschool staff's ratings of social communication and interaction (SCI) and restricted and repetitive behaviors (RRBs) in 3-year-old siblings of children with ASD, either diagnosed (n = 12) or not diagnosed (n = 36) with…

No studies to date have prospectively examined early autism spectrum disorder (ASD) markers in infants with fragile X syndrome (FXS), who are at elevated risk for ASD. This paper describes the developmental profiles of eight infants with FXS from 9 to 24 months of age. Four meet diagnostic criteria for ASD at 24 months of age, and four do not.…

We investigate two aspects of the autism triad, communication and social difficulties, in relatives of specific language impairment (SLI) probands (with and without additional autistic symptomatology) as compared to relatives of autism spectrum disorder (ASD) and Down's syndrome (DS) probands. Findings involving 726 first degree relatives of 85…

We developed and evaluated a new parent report instrument--Parent Observation of Early Markers Scale (POEMS)--to monitor the behavioral development of infants at risk for autism spectrum disorder (ASD) because they have older affected siblings. Parents of 108 at-risk infants (74 males, 34 females) completed the POEMS from child age 1-24 months.…