Differences and Similarities in Predictors of Expressive Vocabulary Development between Children with Down Syndrome and Young Typically Developing Children.

The purpose of this study was to examine potential differences in the predictors of expressive vocabulary development between children with Down syndrome and typically developing children to support preparation for intervention development. An age cohort of 43 children with Down syndrome and 57 typically developing children with similar nonverbal mental age levels were assessed at three time points. Linear mixed models were used to investigate the predictors of expressive vocabulary over time. Both groups achieved progress in expressive vocabulary. The typically developing children had steeper growth than the children with Down syndrome (1.38 SD vs. 0.8 SD, p < 0.001). In both groups, receptive vocabulary, auditory memory, and the home literacy environment were significant predictors of development. In the children with Down syndrome, the phonological awareness and oral motor skills were also significant. Group comparisons showed that receptive vocabulary, auditory memory and oral motor skills were stronger predictors in the children with Down syndrome than in the typically developing children. These results indicate that children with Down syndrome are more vulnerable when it comes to risk factors that are known to influence expressive vocabulary than typically developing children. Children with Down syndrome therefore require early broad-based expressive vocabulary interventions.

The profile of social functioning in children with Down syndrome.

BACKGROUND: Practitioners and researchers have asserted for decades that social functioning is a strength in children with Down syndrome (DS). Nevertheless, some studies have concluded that children with DS may be at greater risk of impaired social functioning compared to typically developing controls. This cross-sectional study explores the profile of social functioning (social capabilities and social problems) in six-year-old children with DS, compares it with that of typically developing children and reveals possible differences in predictors between groups. METHOD: Parental reports and clinical tests were utilized. RESULTS: The children with DS had generally weaker social capabilities compared to nonverbal mental age-matched controls, but no significant differences were found for social interactive play, community functioning and prosocial behaviour. No significant differences in predictors for social capabilities between the groups were found. The children with DS had more social problems than the typically developing controls with a similar chronological age and those with a similar nonverbal mental age, but no significant differences in emotional symptoms were found between the children with DS and either comparison group. Vocabulary was a more important predictor of social problems in the children with DS than in the typically developing control groups. CONCLUSION: Interventions for children with DS should strongly focus on integrating vocabulary skills and social functioning starting at an early age. Implications for Rehabilitation Children with Down syndrome need help and support in social functioning. Systematic training to optimize social capabilities and to prevent social problems should be prioritized. Structured and explicit learning of words important for social interaction with peers and for conflict solutions should be emphasized. Integrated interventions focusing on social functioning and vocabulary should begin in preschool to prepare children for participation in mainstream education.