Do Senior Safety Zones Make a Difference? : A Causal Evaluation of Crash Reduction in Seoul

• In Event: Evidence-based Govenrance and Policy for Health, Energy, and Environment in South Korea

Abstract

Despite continued policy efforts, traffic crashes involving older pedestrians remain a pressing issue in South Korea. Since 2007, the government has introduced senior safety zones to mitigate these risks through localized interventions such as speed reductions, signage, and no stopping. However, few empirical studies have rigorously evaluated the effectiveness of these zones, and most existing research focuses on short-term outcomes during the early years of the policy. Critically, prior studies have not established causal impacts, largely due to methodological limitations such as the absence of appropriate control groups and failure to account for variation in treatment timing.

This study addresses these gaps by estimating the causal effect of senior safety zones on elderly-involved traffic crashes using a staggered difference-in-differences (DiD) design. Zone-level panel data, including the installation year of each zone, are used to define treatment areas within a 300-meter buffer. Matched control areas—comparable in demographic and built environment characteristics but without zone designation—serve as counterfactuals. By leveraging variation in installation timing across zones, the staggered DiD framework allows for a more robust identification of policy effects than conventional DiD approaches.

Preliminary results show no statistically significant reduction in elderly-involved crashes following zone implementation, suggesting that current designation practices may have limited effectiveness. Additional spatial analyses further reveal that many senior safety zones are not optimally located near actual crash hotspots. These findings point to the need for more evidence-based and spatially targeted strategies to improve pedestrian safety for older adults.

Author

• Eun Jin Shin, Sungkyunkwan University
  Presenting Author