title: Modelling the effect on injuries and fatalities when changing mode of transport from car to bicycle.
abstract: BACKGROUND
  Several studies have estimated the health effects of active commuting, where a transport mode shift from car to bicycle reduces risk of mortality and morbidity. Previous studies mainly assess the negative aspects of bicycling by referring to fatalities or police reported injuries. However, most bicycle crashes are not reported by the police and therefore hospital reported data would cover a much higher rate of injuries from bicycle crashes. The aim of the present study was to estimate the effect on injuries and fatalities from traffic crashes when shifting mode of transport from car to bicycle by using hospital reported data.
  
  
  METHODS
  This present study models the change in number of injuries and fatalities due to a transport mode change using a given flow change from car to bicycle and current injury and fatality risk per distance for bicyclists and car occupants.
  
  
  RESULTS
  show that bicyclists have a much higher injury risk (29 times) and fatality risk (10 times) than car occupants. In a scenario where car occupants in Stockholm living close to their work place shifts transport mode to bicycling, injuries, fatalities and health loss expressed in Disability-Adjusted Life Years (DALY) were estimated to increase. The vast majority of the estimated DALY increase was caused by severe injuries and fatalities and it tends to fluctuate so that the number of severe crashes may exceed the estimation with a large margin.
  
  
  CONCLUSIONS
  Although the estimated increase of traffic crashes and DALY, a transport mode shift is seen as a way towards a more sustainable society. Thus, this present study highlights the need of strategic preventive measures in order to minimize the negative impacts from increased bicycling.
authors.affiliation: Folksam Reasearch, Bohusgatan 14, 10660 Stockholm, Sweden. Electronic address: Philip.k.nilsson@gmail.se.
authors.forename: Philip
authors.initials: P
authors.lastname: Nilsson
authors.affiliation: Folksam Reasearch, Bohusgatan 14, 10660 Stockholm, Sweden; Department of Applied Mechanics, Chalmers University of Technology, Hörsalsvägen 7a, 96 Gothenburg, Sweden. Electronic address: Helena.stigson@folksam.se.
authors.forename: Helena
authors.initials: H
authors.lastname: Stigson
authors.affiliation: Department of Applied Mechanics, Chalmers University of Technology, Hörsalsvägen 7a, 96 Gothenburg, Sweden; Department of Food and Nutrition and Sport Science, University of Gothenburg, Läroverksgatan 5, 40530 Gothenburg, Sweden. Electronic address: Maria.ohlin@gu.se.
authors.forename: Maria
authors.initials: M
authors.lastname: Ohlin
authors.affiliation: Department of Applied Mechanics, Chalmers University of Technology, Hörsalsvägen 7a, 96 Gothenburg, Sweden; Swedish Transport Administration, Röda vägen 1, 781 70 Borlänge, Sweden. Electronic address: Johan.strandroth@trafikverket.se.
authors.forename: Johan
authors.initials: J
authors.lastname: Strandroth
mesh_terms: D000063:Accidents, Traffic / Q000401:mortality*; D001642:Bicycling / Q000293:injuries*; D006801:Humans; D018570:Risk Assessment; D012449:Safety; D014186:Transportation / Q000706:statistics & numerical data; D017132:Workplace; D014947:Wounds and Injuries / Q000401:mortality*
keywords: Bicycle injuries; Car injuries; DALY; Modelling; Transport mode change