Urban areas in North American cities with positive trends in bicycle usage also witness a high number ofcyclist injuries every year. Previous cyclist safety studies based on the traditional approach, which relieson historical crash data, are known to have some limitations such as the fact that crashes need to happen(a reactive approach). This paper explores the use of GPS deceleration events as a surrogate-proactivemeasure and investigates the relationship between reported cyclist road injuries and deceleration events.The surrogate safety measure is defined based on deceleration values representing hard breaking situ-ations. This work uses a large sample of GPS cyclist trip data from a smartphone application to extractdeceleration rates at intersections and along segments and to explore its relationship with the numberof observed injuries and validate deceleration rate (DR) as a surrogate safety measure. Using Spearman’srank correlation coefficient, we compared the ranking of sites based on the expected number of injuriesand based on DR. The ranks of expected injuries and dangerous decelerations were found to have a cor-relation of 0.60 at signalized intersections, 0.53 at non-signalized intersections and 0.57 at segments.Despite the promising results of this study, more granular data and validation work needs to be done toimprove the reliability of the measures. The technological limitations and future work are discussed atthe end of the paper. (Author/publisher)
Abstract