THE SOCIOECONOMIC GRADIENT IN THE DEVELOPMENTAL HEALTH OF CANADIAN CHILDREN WITH DISABILITIES

Abstract

Background: Compared with typically developing children, children with special needs often struggle with academic and social aspects of school, though certain factors can improve their academic and social developmental trajectory. The objective of this investigation was to explore the association between the developmental health of children with special needs at school-entry, as measured by the Early Development Instrument (EDI), and neighborhood-level SES. To date, the EDI has only been validated for use in typically developing children. Hence, a secondary objective of this investigation was to explore the psychometric properties of the EDI for children with special needs. Methods: The data for this investigation were from the Pan-Canadian database of children’s developmental health at school entry. The psychometric properties of the EDI, including item and domain characteristics, factor structure, and construct validity, were tested for children with special needs. Hierarchical generalized linear models was used to model the association between EDI domain scores and a custom neighborhood SES index. Results: A total of 29,841 (69.8% male) and 29,520 (69.7% male) children with special needs were available for the investigation on the psychometric properties of the EDI and the relationship between EDI outcomes and SES, respectively. The psychometric performance of the EDI in children with special needs was similar to its performance in typically developing children. The EDI was subsequently used to explore the association between developmental outcomes and neighborhood socioeconomic status (SES). All EDI domains were positively correlated with SES, indicating that children in high SES neighborhoods have better developmental outcomes at school entry than those in lower SES neighborhoods. Conclusions: The results of this investigation draw attention to the potential impact of contextual factors on children’s health and have implications for policy development and service planning. These results also indicate that the EDI performs similarly in children with special needs and typically developing children, thus enabling its more extensive use for this population.