Child pedestrian and cyclist injuries, and the built and social environment across Canadian cities: the Child Active Transportation Safety and the Environment Study (CHASE)

INTRODUCTION: Traffic injury is a leading and preventable cause of child death and disability, with child pedestrians and cyclists particularly vulnerable. Examining built environment correlates of child pedestrian and cyclist motor vehicle collisions (PCMVC) in different settings is needed to promote an evidence-based approach to road safety. METHODS: We conducted a cross-sectional study across multiple urban/suburban environments in Canada (Calgary, Toronto, Montreal, Laval, Peel Region). All public elementary schools were included (n=1030). We examined the role of land use/social environments, road environments and traffic safety interventions on the rates of child PCMVC within 1000 m of schools. Multivariable negative binomial regression was conducted for all cities and by individual city. In a subset of schools (n=389), we examined associations when controlling for active school transportation (AST). RESULTS: Mean PCMVC rate per school ranged from 0.13 collisions/year in Peel to 0.35 in Montreal. Child PCMVC were correlated with land use, social and road environments and traffic safety interventions. In fully adjusted models, social and land use features remained the most important correlates. New immigrant population had the largest positive association with child PCMVC (incidence rate ratio (IRR): 1.26, 95% CI 1.06 to 1.50), while old housing (pre-1960) density was most protective (IRR: 0.83, 95% CI 0.77 to 0.90). AST was associated with PCMVC, but it had no effect on the relationships between PCMVC and other social/environmental correlates. CONCLUSION: The built environment and social factors influence rates of child PCMVC. Opportunities to reduce child PCMVC exist through modifications to city design and road environments and implementing traffic safety interventions.