Identification of contributing factors for wrong-way crashes on freeways in Illinois

Abstract

ABSTRACTTo investigate the contributing factors for wrong-way crashes on freeways based on information available from crash databases and crash reports, causal tables and a Haddon matrix are used to analyze fatal and injury-related crashes caused by wrong-way driving from 2004 to 2009 in Illinois. For the first step, causal tables are generated based on the police crash reports, in which the percentage of crashes caused by each factor is calculated. Based on these percentages, the contributing factors are ranked. Next, a Haddon matrix is developed for each wrong-way crash in which different factors are identified separately for periods before, during, and after the crash. These factors include drivers' age, drivers' condition, crash causes, vehicle types, vehicle maneuvers, roadway conditions, weather, and wrong-way entry points. For a crash with multiple contributing factors, a weighted point is calculated and assigned to each factor. The total points for each factor are used to rank the order of all contributing factors. Furthermore, a significance test is used to analyze the statistical significance of each of those factors. The analysis results indicate that alcohol impairment, darkness, and driver's age and skill are among the top contributing factors for wrong-way crashes.