A MODEL FOR PERFORMING STATEWIDE TRAFFIC CRASH ANALYSIS: MICHIGAN EXPERIENCE

Traffic safety professionals are confronted with the problem of mitigating traffic crashes, injuries and fatalities on our highways which are often caused due to the increasing traffic volumes and, in some instances, congestion. These may be reduced through effective statewide safety improvement programs, which require careful investigation and analysis of historical crash data. The authors of this paper were involved in a project in which a statewide traffic crash analysis using crash and exposure data for the entire State of Michigan was performed. The resources available for safety projects and programs are typically not sufficient to pursue a comprehensive set of safety initiatives for the entire state. Therefore, an optimal use of the available resources is necessary to achieve the greatest overall safety benefit. The Office of Highway Safety Planning (OHSP) in Michigan provides funding to local governmental agencies for a variety of safety projects and programs to alleviate traffic crashes and injuries. Most of the projects funded by this agency involve safety initiatives related to alcohol, safety restraint system, enforcement of traffic regulations, and programs related to driver behavior. An important application of the analysis performed by the authors is to evaluate and help prioritize such traffic safety projects and programs. A comprehensive analysis of traffic crashes and injuries was performed using four years of crash data for all eighty three counties in the state. The high priority areas for implementing safety initiatives were identified and prioritized through a Safety Performance Model developed using multiple exposure variables. This paper describes the development, analysis, benefits and uses of the Safety Performance Model.