Quasi-Experimental Analysis of COVID-19 Effects on Older Versus Younger Adults’ Travel Behavior: The Moderating Role of the Built Environment

Using two months of secular cellphone traces from older adults in Shenzhen, China, this study applies an interrupted time-series quasi-experimental design to assess COVID-19’s effects on daily personal kilometers traveled across neighborhoods with varying built environments. Findings reveal that the First-Level Response and Closed-Off Community Management policies had a less pronounced impact on older adults, who experienced a slower decline in mobility and a more gradual postintervention recovery, compared with young adults. Interventions prove notably effective in dense, mixed-use neighborhoods, including unexpectedly so in car-oriented areas with limited intersections and beyond city centers. These insights are vital for developing age-sensitive mobility policies and built environments in response to public health crises.