Nonlinear effects of built environment on road traffic safety: A multi-scale perspective

First, drivers' visual information (captured <i>via</i> SVIs) emerged as the most critical factor, contributing 74.08% to road safety outcomes. Second, tunnels, primary roads, residential roads, all POI categories, guardrails, and traffic signals were identified as significant hazards. Moreover, SVI features and road class exhibited pronounced nonlinear effects on safety. Additionally, significant interaction effects were observed between these variables, indicating that their combined influence on safety is more complex than individual effects alone.