On-Road Bicycle Facilities and Cyclist Injury in Bicycle-Motor Vehicle Crashes in Chicago

Bicycling has been increasing in North America, in particular for utilitarian trips and in urban areas. Infrastructure changes such as on- and off-road bicycle lanes, routes, and paths have been implemented in many cities to accommodate growing numbers of cyclists. Risk perceptions deter many more potential cyclists concerned about collisions with motor vehicles. This cross-sectional study examined road crashes between motor vehicles and bicycles from 2008–2010 in the city of Chicago using traffic crash report data. Geographic Information Systems files containing on-road bicycle facilities (i.e., designated bike lanes, marked shared lanes, or signed recommended bike routes) and bus stops were obtained from the city of Chicago and spatially matched to crash locations. Logistic regression was used to examine the relationship between presence of each type of bike facility and bus stop with occurrence of an incapacitating or fatal injury to the cyclist, a dichotomous variable, separately for intersection and non-intersection crashes. Nearly three-fifths of the crashes were intersection-related but severe injury prevalence did not vary between intersection and non-intersection crashes. There were significantly more intersection crashes on or near recommended bike routes, while greater percentages of non-intersection crashes occurred near bike lanes and marked shared lanes. There were no statistically significant bivariate associations between the presence of any bicycle facility or bus stop and severe cyclist injury. In multivariable models, only presence of a recommended bike route was significantly negatively associated with severe cyclist injury for intersection crashes, and a designated bike lane was marginally negatively associated with severe injury in non-intersection crashes. Presence of a marked shared lane was not associated with the injury measure. Bicycle facilities and posted signage may lead drivers to anticipate cyclist presence and bicycle lanes may allow for greater distance between motor vehicles and bicycles at non-intersection locations. This study lends limited support to previous research suggesting that roadways with bicycle facilities may be safer for cyclists than untreated roadways. However, caution should be taken when interpreting results from injury studies using traffic crash report data due to potentially poor reliability of police injury assessments.