Behavior predictors of language development over 2 years in children with autism spectrum disorders.
OBJECTIVE
This exploratory study examined predictive relationships between 5 types of behaviors and the trajectories of vocabulary and language development in young children with autism over 2 years.


METHODS
Participants were 69 children with autism assessed using standardized measures prior to the initiation of early intervention (T1) and 6 months (T2), 12 months (T3), and 24 months (T4) later. Growth curve modeling examined the extent to which behaviors at T1 and changes in behaviors between T1 and T2 predicted changes in development from T1 to T4.


RESULTS
Regardless of T1 nonverbal IQ and autism severity, high scores for inattentive behaviors at T1 predicted lower rates of change in vocabulary production and language comprehension over 2 years. High scores for social unresponsiveness at T1 predicted lower rates of change in vocabulary comprehension and production and in language comprehension over 2 years. Scores for insistence on sameness behaviors, repetitive stereotypic motor behaviors, and acting-out behaviors at T1 did not predict the rate of change of any child measure over 2 years beyond differences accounted for by T1 autism severity and nonverbal IQ status.


CONCLUSIONS
The results are discussed with regard to their implications for early intervention and understanding the complex factors that affect developmental outcomes.
The University of British Columbia, 2125 Main Mall, Vancouver, BC, Canada, V6T 1Z4. bopp@interchange.ubc.ca
Karen D
KD
Bopp
Pat
P
Mirenda
Bruno D
BD
Zumbo
D000184:Acting Out; D001321:Autistic Disorder / Q000150:complications* / Q000175:diagnosis*; D002648:Child; D002653:Child Behavior Disorders / Q000175:diagnosis / Q000209:etiology; D002675:Child, Preschool; D016208:Databases, Factual; D005260:Female; D006801:Humans; D007223:Infant; D007804:Language Development; D007805:Language Development Disorders / Q000175:diagnosis* / Q000209:etiology*; D008297:Male; D008960:Models, Psychological; D011237:Predictive Value of Tests; D012720:Severity of Illness Index; D019956:Stereotypic Movement Disorder / Q000175:diagnosis / Q000209:etiology; D014825:Vocabulary