Age of symptom onset in young children with pervasive developmental disorders.

Data from 39 young children with autism or other pervasive developmental disorders were examined to determine the relevance of the age of social symptom onset and language symptom onset to other developmental variables. Contrary to the authors' hypotheses, earlier onset of social symptoms was not indicative of a greater severity of autistic symptoms, retardation, or incidence of insecure attachments. Early speech loss was associated with lower IQ, greater social deficits, and poorer language development, while the presence of useful speech at age 2 was related to better functioning in multiple domains. Thus, language functions, rather than the social behaviors examined, carried the greatest predictive power regarding short-term outcomes.