Study Details

Study Title: Exposure Measures and Injury Frequency Models for Analysis of Cyclist Safety at Signalized Intersections

Authors: Miranda-Moreno et al.

Publication Date: JAN, 2011

Abstract: To address the rising issue of cyclist safety at signalized intersections, establishing the relationship between motor-vehicle and cyclist flows, geometric design and built environment characteristics is fundamental. To date, there is very little empirical evidence of the impact of these factors on cyclist injury occurrence and on the most effective countermeasures in North America. In this regard, this research (i) proposes a new approach to measure risk exposure and (ii) develops cyclist injury frequency models. Three separate definitions of risk exposure are used: completely aggregated flows, motor-vehicle flows aggregated by movement type and potential conflicts between motor vehicles and cyclists. As an application environment, a sample of signalized intersections on the island of Montreal was used, as well as data comprising of disaggregate motor-vehicle and cyclist flows. Several negative binomial models were fitted to the data. Among the results, this study shows that cyclist collisions are sensitive to changes in cyclist flows: a 10% increase in bicycle flow is associated with a 5.3% increase in the frequency of cyclist injuries. Surprisingly, motor-vehicle volumes at the intersection level do not have a significant effect on cyclist collision frequency. However, when motor-vehicle flows are considered based on movement type, it becomes apparent that right turn movements have a great effect on accident occurrence. Similar results, indentifying right turns as having the greatest effect on cyclist injuries, are achieved when potential conflicts are considered. It was also found that the number of bus stops in the proximity of intersections increases cyclist injury occurrence. Some geometric design factors such as presence of median and three-leg intersections were tested; however, their effect was found to be statistically non-significant.

Study Citation: Miranda-Moreno, L., Strauss, J., and Morency, P., "Exposure Measures and Injury Frequency Models for Analysis of Cyclist Safety at Signalized Intersections." Presented at the 90th Meeting of the Transportation Research Board, Washington, D.C., (2011).


CMFs Associated With This Study

Category: Access management

Countermeasure: Presence of median

CMF CRF(%) Quality Crash Type Crash Severity Roadway Type Area Type
0.97 3.1 3 Stars Vehicle/bicycle All Not Specified Urban and suburban

Countermeasure: Presence of parking entrances

CMF CRF(%) Quality Crash Type Crash Severity Roadway Type Area Type
1.01 -0.5 3 Stars Vehicle/bicycle All Not Specified Urban and suburban

Category:Intersection geometry

Countermeasure: Presence of three leg intersection vs. four leg intersection

CMF CRF(%) Quality Crash Type Crash Severity Roadway Type Area Type
0.86 13.8 3 Stars Vehicle/bicycle All Not Specified Urban and suburban

Category:Pedestrians

Countermeasure: Change number of bus stops in 50m buffer from X to Y

CMF CRF(%) Quality Crash Type Crash Severity Roadway Type Area Type
CMF Equation CRF Equation 3 Stars Vehicle/bicycle All Not Specified Urban and suburban