Incorporating the Safe System and sociodemographics into the built environment model of traffic safety: A Transtheoretical Model

In recent years, transportation engineering theory of the built environment has paid increased attention to land planning organisation and urban design in preventing traffic crashes. Empirical investigations have been conducted into the relationships between built environment factors and crash occurrence and severity. However, there is a lack of closer examination on the interactions among built environment factors and the safe system approach that is considered ‘best practice’ in road safety. There is also a lack of attention to how sociodemographic factors might influence built environment factors at the micro and macro level, as well as the safe system. The objective of this research was to make explicit the multiple pathways through which the built environment potentially affects risk of crash incorporating theories of the role of sociodemographics and the safe system. A transtheoretical model is proposed developed from Ewing and Dumbaugh’s (2009) conceptual framework linking the built environment to traffic safety to incorporate the road safety framework of the ‘safe system’ components of safe roads and roadsides, safe speeds, safe road users and safe vehicles, as well as key sociodemographics based on a review of empirical research from urban planning, transport and road safety literature. A transtheoretical model is proposed to point to the importance of future efforts integrating road safety theory into built environment planning work and engineering designs.