Use of a driving simulator to assess risk of bicycle-motor vehicle crashes

Background/Purpose Bicycling is an active and sustainable form of transportation, but may entail substantial motor vehicle-related injury risks. These risks are very difficult to assess in situ. Our study used a driving simulator to quantitatively evaluate bicycle-motor vehicle (BMV) crash risk associated with different road characteristics.

Methods Thirty adult subjects drove a predefined simulated route through various urban, suburban, and rural environments with and without the presence of virtual bicyclists. Outcomes assessed were BMV separation (a measure of crash risk) and vehicle speed (a measure of potential crash severity).  Subjects also completed a survey that assessed demographics, driving experience, driving-related knowledge, attitudes, and behaviors, and risk-taking behaviors.

Results/Outcomes We found that bicycle lanes and, to a lesser extent, bicycle signage may reduce crash risk by increasing BMV separation and reducing vehicle speeds near bicycles. Four-lane roads had substantially increased BMV separation (e.g., reduced crash risk) when compared to two lane roads, but also had increased vehicle speeds (greater potential crash severity).  Conversely, vehicle speeds near bicyclists on roads with curbs were reduced, but BMV separation was diminished. Regression model results showed that older and male drivers had decreased risk of BMV crash, while drivers with a greater number of lifetime crashes and poor lane keeping ability had increased risk. 

Conclusions This study demonstrated that automobile simulator technology can be used to evaluate the efficacy of bicycle safety interventions and roadway configurations in a controlled and repeatable manner and without the difficulties associated with in situ measurements.