Autism spectrum disorders (ASD) often go undetected in toddlers. The Modified Checklist for Autism in Toddlers (M-CHAT) was used to screen 3,793 children aged 16-30 months from lowand high-risk sources; screen positive cases were diagnostically evaluated. Re-screening was performed on 1,416 children aged 42-54 months. Time 1 Positive Predictive Value (PPV) was .36 for the initial screening and .74 for the screening plus follow-up telephone interview; values were similar for Time 2 PPV. When separating referral sources, PPV was low for the low-risk sample but acceptable with the follow-up telephone interview. Children with ASD from the low-risk and high-risk samples were highly similar. Results indicate that the M-CHAT continues to be a promising instrument for the early detection of ASD.

A diagnosis of autism spectrum disorder (ASD) is usually taken to be permanent. In this study, 13 two-year-old children with ASD lost the diagnosis by age 4, at which time they scored within the normal range on standardized measures of cognitive and adaptive functioning. No differences were found in symptom severity, socialization, or communication between children who lost the ASD diagnosis and children who did not, but children with PDD-NOS were significantly more likely than those with full autistic disorder to move off the spectrum. The clearest distinguishing factor was motor skills at age 2. Results support the idea that some toddlers with ASD can lose their diagnosis and suggest that this is difficult to predict.

This study compared behavioral presentation of toddlers with autistic spectrum disorders (ASD) and toddlers with global developmental delay (DD) or developmental language disorder (DLD) who display some characteristics of ASD using the diagnostic algorithm items from the Autism Diagnostic Observation Schedule, Generic (ADOS), the Childhood Autism Rating Scale (CARS), and Modified Checklist for Autism in Toddlers (M-CHAT). To date, 195 children have failed the M-CHAT and have been diagnosed with ASD, DD or DLD. Children with ASD had prominent and consistent impairments in socialization skills, especially joint attention skills and were more impaired in some aspects of communication, play, and sensory processing. Children with ASD and children with DD/DLD shared common features, but certain behavioral markers differentiated the two groups.

No abstract