title: Bicycle Use and Cyclist Safety Following Boston's Bicycle Infrastructure Expansion, 2009-2012.
abstract: OBJECTIVE
  To evaluate changes in bicycle use and cyclist safety in Boston, Massachusetts, following the rapid expansion of its bicycle infrastructure between 2007 and 2014.
  
  
  METHODS
  We measured bicycle lane mileage, a surrogate for bicycle infrastructure expansion, and quantified total estimated number of commuters. In addition, we calculated the number of reported bicycle accidents from 2009 to 2012. Bicycle accident and injury trends over time were assessed via generalized linear models. Multivariable logistic regression was used to examine factors associated with bicycle injuries.
  
  
  RESULTS
  Boston increased its total bicycle lane mileage from 0.034 miles in 2007 to 92.2 miles in 2014 (P < .001). The percentage of bicycle commuters increased from 0.9% in 2005 to 2.4% in 2014 (P = .002) and the total percentage of bicycle accidents involving injuries diminished significantly, from 82.7% in 2009 to 74.6% in 2012. The multivariable logistic regression analysis showed that for every 1-year increase in time from 2009 to 2012, there was a 14% reduction in the odds of being injured in an accident.
  
  
  CONCLUSIONS
  The expansion of Boston's bicycle infrastructure was associated with increases in both bicycle use and cyclist safety.
authors.affiliation: All of the authors are with the Harvard T. H. Chan School of Public Health, Boston, MA. Felipe E. Pedroso is also with the Department of Surgery, New York Presbyterian Hospital, Columbia University Medical Center, New York, NY.
authors.forename: Felipe E
authors.initials: FE
authors.lastname: Pedroso
authors.affiliation: All of the authors are with the Harvard T. H. Chan School of Public Health, Boston, MA. Felipe E. Pedroso is also with the Department of Surgery, New York Presbyterian Hospital, Columbia University Medical Center, New York, NY.
authors.forename: Federico
authors.initials: F
authors.lastname: Angriman
authors.affiliation: All of the authors are with the Harvard T. H. Chan School of Public Health, Boston, MA. Felipe E. Pedroso is also with the Department of Surgery, New York Presbyterian Hospital, Columbia University Medical Center, New York, NY.
authors.forename: Alexandra L
authors.initials: AL
authors.lastname: Bellows
authors.affiliation: All of the authors are with the Harvard T. H. Chan School of Public Health, Boston, MA. Felipe E. Pedroso is also with the Department of Surgery, New York Presbyterian Hospital, Columbia University Medical Center, New York, NY.
authors.forename: Kathryn
authors.initials: K
authors.lastname: Taylor
mesh_terms: D000059:Accidents / Q000639:trends*; D001642:Bicycling; D001900:Boston; D016208:Databases, Factual; D004779:Environment Design / Q000639:trends*; D006801:Humans; D016015:Logistic Models; D012449:Safety