Testing Predictive Validity of the Communication Composite of the Communication and Symbolic Behavior Scales

Abstract
This study tested the predictive validity of the Communication Composite of the Communication and Symbolic Behavior Scales as a predictor of expressive vocabulary. The Communication Composite consists of six clusters that measure specific aspects of communicative behavior. Participants were 58 children, 17 to 34 months of age, who were functioning at the prelinguistic stage of language development. All children had mild to moderate developmental delays but no sensory impairments. The Communication Composite was used to measure prelinguistic communication skills at the beginning of the study, and an unstructured play session was used to measure expressive vocabulary 1 year later. Results indicated that the Communication Composite was a significant predictor of later expressive language. In addition, all tested clusters were significant predictors of later expressive language.