Risk markers for poor developmental attainment in young children: results from a longitudinal national survey.

Objective: To evaluate social and environmental determinants of poor developmental attainment among preschool children by means of longitudinal data from a population-based sample of Canadian children.

Design: Secondary analysis of data from cycles 1 (1994-1995) and 2 (1996-1997) of the National Longitudinal Survey of Children and Youth using a cohort design with 2-year follow-up.

Participants: A total of 4987 children aged 1 to 5 years at baseline, whose biological mother completed risk factor information and who were included in both cycles.

Main Outcome Measures: Poor developmental attainment (developing unusually slowly) was defined as scores more than 1 SD below the age-standardized mean for the Motor and Social Development Scale, revised Peabody Picture Vocabulary Test, or Canadian Achievement Tests in mathematics and reading/comprehension, depending on the child's age.

Results: The prevalence of sustained poor developmental attainment after 2 years of follow-up was 4.6%. Factors found to be associated with poor developmental attainment included male sex (odds ratio [OR], 1.37; 95% confidence interval [CI], 1.10-1.70), maternal depression (OR, 1.64; 95% CI, 1.25-2.15), low maternal education (OR, 1.57; 95% CI, 1.19-2.08), maternal immigrant status (OR, 1.93; 95% CI, 1.38-2.71), and household low income adequacy (OR, 1.43; 95% CI, 1.11-1.83).

Conclusions: Having a mother who has symptoms of depression, has low education, or is an immigrant, and living in a household with low income adequacy increase the risk of poor developmental attainment in children aged 1 to 5 years. The notable risks associated with these factors indicate them as possible targets for screening and interventions to prevent poor developmental attainment.