title: Health impact assessment of active transportation: A systematic review.
abstract: OBJECTIVE
  Walking and cycling for transportation (i.e. active transportation, AT), provide substantial health benefits from increased physical activity (PA). However, risks of injury from exposure to motorized traffic and their emissions (i.e. air pollution) exist. The objective was to systematically review studies conducting health impact assessment (HIA) of a mode shift to AT on grounds of associated health benefits and risks.
  
  
  METHODS
  Systematic database searches of MEDLINE, Web of Science and Transportation Research International Documentation were performed by two independent researchers, augmented by bibliographic review, internet searches and expert consultation to identify peer-reviewed studies from inception to December 2014.
  
  
  RESULTS
  Thirty studies were included, originating predominantly from Europe, but also the United States, Australia and New Zealand. They compromised of mostly HIA approaches of comparative risk assessment and cost-benefit analysis. Estimated health benefit-risk or benefit-cost ratios of a mode shift to AT ranged between -2 and 360 (median=9). Effects of increased PA contributed the most to estimated health benefits, which strongly outweighed detrimental effects of traffic incidents and air pollution exposure on health.
  
  
  CONCLUSIONS
  Despite different HIA methodologies being applied with distinctive assumptions on key parameters, AT can provide substantial net health benefits, irrespective of geographical context.
authors.affiliation: Centre for Research in Environmental Epidemiology (CREAL), C/Dr. Aiguader 88, 08003 Barcelona, Spain; Universitat Pompeu Fabra (UPF), C/Dr. Aiguader 88, 08003 Barcelona, Spain; CIBER Epidemiología y Salud Pública (CIBERESP), C/Monforte de Lemos 3-5, 28029 Madrid, Spain. Electronic address: nmueller@creal.cat.
authors.forename: Natalie
authors.initials: N
authors.lastname: Mueller
authors.affiliation: Centre for Research in Environmental Epidemiology (CREAL), C/Dr. Aiguader 88, 08003 Barcelona, Spain; Universitat Pompeu Fabra (UPF), C/Dr. Aiguader 88, 08003 Barcelona, Spain; CIBER Epidemiología y Salud Pública (CIBERESP), C/Monforte de Lemos 3-5, 28029 Madrid, Spain.
authors.forename: David
authors.initials: D
authors.lastname: Rojas-Rueda
authors.affiliation: Centre for Research in Environmental Epidemiology (CREAL), C/Dr. Aiguader 88, 08003 Barcelona, Spain; Universitat Pompeu Fabra (UPF), C/Dr. Aiguader 88, 08003 Barcelona, Spain; CIBER Epidemiología y Salud Pública (CIBERESP), C/Monforte de Lemos 3-5, 28029 Madrid, Spain.
authors.forename: Tom
authors.initials: T
authors.lastname: Cole-Hunter
authors.affiliation: Centre for Environmental Policy, Imperial College London, Exhibition Road, South Kensington Campus, SW7 2AZ London, United Kingdom.
authors.forename: Audrey
authors.initials: A
authors.lastname: de Nazelle
authors.affiliation: Flemish Institute for Technological Research (VITO), Boeretang 200, 2400 Mol, Belgium; Centre for Environmental Sciences, Hasselt University, Agoralaan building D, 3590 Diepenbeek, Belgium.
authors.forename: Evi
authors.initials: E
authors.lastname: Dons
authors.affiliation: University of Natural Resources and Life Sciences Vienna, Institute for Transport Studies, Peter-Jordan-Straße 82, 1190 Vienna, Austria.
authors.forename: Regine
authors.initials: R
authors.lastname: Gerike
authors.affiliation: Physical Activity and Health Unit, Epidemiology, Biostatistics and Prevention Institute, University of Zurich, Seilergraben 49, 8001 Zurich, Switzerland.
authors.forename: Thomas
authors.initials: T
authors.lastname: Götschi
authors.affiliation: Flemish Institute for Technological Research (VITO), Boeretang 200, 2400 Mol, Belgium; School for Mobility, Hasselt University, Wetenschapspark, 3590 Diepenbeek, Belgium.
authors.forename: Luc
authors.initials: L
authors.lastname: Int Panis
authors.affiliation: Physical Activity and Health Unit, Epidemiology, Biostatistics and Prevention Institute, University of Zurich, Seilergraben 49, 8001 Zurich, Switzerland.
authors.forename: Sonja
authors.initials: S
authors.lastname: Kahlmeier
authors.affiliation: Centre for Research in Environmental Epidemiology (CREAL), C/Dr. Aiguader 88, 08003 Barcelona, Spain; Universitat Pompeu Fabra (UPF), C/Dr. Aiguader 88, 08003 Barcelona, Spain; CIBER Epidemiología y Salud Pública (CIBERESP), C/Monforte de Lemos 3-5, 28029 Madrid, Spain.
authors.forename: Mark
authors.initials: M
authors.lastname: Nieuwenhuijsen
mesh_terms: D001642:Bicycling; D015444:Exercise; D005260:Female; D062489:Health Impact Assessment; D006801:Humans; D008297:Male; D018570:Risk Assessment; D014186:Transportation / Q000379:methods*; D016138:Walking
keywords: Active transportation; Air pollution; Health impact assessment; Mode shift; Physical activity; Traffic incident