title: Evaluating the safety effects of bicycle lanes in New York City.
abstract: OBJECTIVE
  We evaluated the effects of on-street bicycle lanes installed prior to 2007 on different categories of crashes (total crashes, bicyclist crashes, pedestrian crashes, multiple-vehicle crashes, and injurious or fatal crashes) occurring on roadway segments and at intersections in New York City.
  
  
  METHODS
  We used generalized estimating equation methodology to compare changes in police-reported crashes in a treatment group and a comparison group before and after installation of bicycle lanes. Our study approach allowed us to control confounding factors, such as built environment characteristics, that cannot typically be controlled when a comparison group is used.
  
  
  RESULTS
  Installation of bicycle lanes did not lead to an increase in crashes, despite the probable increase in the number of bicyclists. The most likely explanations for the lack of increase in crashes are reduced vehicular speeds and fewer conflicts between vehicles and bicyclists after installation of these lanes.
  
  
  CONCLUSIONS
  Our results indicate that characteristics of the built environment have a direct impact on crashes and that they should thus be controlled in studies evaluating traffic countermeasures such as bicycle lanes. To prevent crashes at intersections, we recommend installation of "bike boxes" and markings that indicate the path of bicycle lanes across intersections.
authors.affiliation: Department of Civil Engineering, City College of New York, New York, NY, USA.
authors.forename: Li
authors.initials: L
authors.lastname: Chen
authors.forename: Cynthia
authors.initials: C
authors.lastname: Chen
authors.forename: Raghavan
authors.initials: R
authors.lastname: Srinivasan
authors.forename: Claire E
authors.initials: CE
authors.lastname: McKnight
authors.forename: Reid
authors.initials: R
authors.lastname: Ewing
authors.forename: Matthew
authors.initials: M
authors.lastname: Roe
mesh_terms: D000063:Accidents, Traffic / Q000517:prevention & control / Q000706:statistics & numerical data*; D001642:Bicycling / Q000706:statistics & numerical data*; D004779:Environment Design; D006801:Humans; D015233:Models, Statistical; D009519:New York City; D011156:Population Density; D012449:Safety
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