Safely active mobility for urban baby boomers: The role of neighborhood design

•Better land use diversity, intersection density, and accessibilities to retail shops tend to increase walking activities.•Accessibility to retail shops, as well as speed limits and traffic volumes, are associated with traffic crash frequency.•Traffic crash frequency in a neighborhood is negatively correlated with older residents’ walking activity levels. Many urban designers and researchers argue that walkable urban environments can encourage older residents’ walking activities that benefit their physical health. However, walking also exposes older adults to safety risks, including due to traffic accidents. This study seeks to reveal the interactions between urban form and safety affecting urban baby boomers’ walking behavior. Spatial analysis reveals traffic collision patterns in urban Boston neighborhoods, detecting hotspots around activity centers. Structural equation modeling, estimated on individual data collected from a mail-back survey and utilizing numerous measures of neighborhood urban form and accessibility, then attempts to reveal the causal, interacting relationships between neighborhood-level urban form, traffic crashes, and baby boomers’ walking behavior. The analysis identifies significant effects of walkable urban forms (e.g., mixed use, well-connected streets, and good access to potential destinations) on older adults’ walking. Yet, accessibility to retail, as well as traffic speed and volume, are positively associated with the traffic collision frequency. The results suggest more cautious approaches may be necessary for designing urban spaces for walkability and also call into question prescriptions based on the “safety in numbers” hypothesis.