Abstract
This study examined adaptive behavior and cognitive skills for 125 toddlers on the autism spectrum using the recently updated Vineland-II and Bayley-III. Delays in adaptive skills were apparent at 2 years of age. As a group, toddlers on the autism spectrum had a profile of Vineland-II standard scores in which Motor Skills > Daily Living Skills > Socialization > Communication. Vineland-II scores were significantly correlated with Bayley-III Cognitive scores. Performance on the ADOS was significantly negatively correlated with Bayley-III Cognitive standard scores and standard scores in the Daily Living Skills and Communication domains of the Vineland-II. However, calibrated ADOS scores did not contribute significant variance to Vineland-II scores beyond that predicted by age and Bayley-III scores.