Comparison of Autism Screening in Younger and Older Toddlers.

This study examined the effect of age at completion of an autism screening test on item failure rates contrasting older (>20 months) with younger (<20 months) toddlers in a community primary care sample of 73,564 children. Items related to social development were categorized into one of three age sets per criteria from Inada et al. (Research in Autism Spectrum Disorders 4(4):605-611, 2010). Younger toddlers produced higher rates of item failure than older toddlers and items in both of the later acquired item sets had higher probability rates for failure than the earliest acquired item set (prior to 8 months). Use of the same items and the same scoring throughout the target age range for autism screening may not be the best strategy for identifying the youngest toddlers at risk for autism.