This study found that 16 preschoolers with Down's syndrome attained higher age equivalents and standard scores in "socialization" than did 16 preschoolers with autism. Adaptive age equivalent was positively related to chronological age for children with Down's syndrome in all domains, but only in "communication" for children with autism.…

Sixteen individuals with autism and sixteen with Down's Syndrome, aged 10-29, were matched for verbal mental age. The groups' scores did not differ on the Vineland Adaptive Behavior Scales. However, the adaptive skills of Down's Syndrome individuals kept pace with mental age, while the skills of autistic subjects did not change. (Author/JDD)