This just in, a great study from researchers at the Center for Research in Environmental Epidemiology in Barcelona, Spain examines the health impact (operationalized by all cause mortality) of the Bicing public bicycle share program. Bottom line, as confirmed by a few other modeling studies (see here for example) is that despite risks associated with exposure to air pollution and collisions, the physical activity benefits of cycling for transport vastly outweigh the risks. This is study is very interesting because, as the authors mention, they evaluate an actual intervention while most modeling studies simply assume different scenarios. The challenge with assuming scenarios is that although we estimate that cycling is good, we don’t actually know how to bring about increases in cycling or decreases in private motor vehicle use. Here is the abstract. Read the article here (Woot to BMJ for being open access).
Health Impact Assessement of Bike Sharing
Objective To estimate the risks and benefits to health of travel by bicycle, using a bicycle sharing scheme, compared with travel by car in an urban environment.
Design Health impact assessment study.
Setting Public bicycle sharing initiative, Bicing, in Barcelona, Spain.
Participants 181 982 Bicing subscribers.
Main outcomes measures The primary outcome measure was all cause mortality for the three domains of physical activity, air pollution (exposure to particulate matter <2.5 µm), and road traffic incidents. The secondary outcome was change in levels of carbon dioxide emissions.
Results Compared with car users the estimated annual change in mortality of the Barcelona residents using Bicing (n=181 982) was 0.03 deaths from road traffic incidents and 0.13 deaths from air pollution. As a result of physical activity, 12.46 deaths were avoided (benefit:risk ratio 77). The annual number of deaths avoided was 12.28. As a result of journeys by Bicing, annual carbon dioxide emissions were reduced by an estimated 9 062 344 kg.
Conclusions Public bicycle sharing initiatives such as Bicing in Barcelona have greater benefits than risks to health and reduce carbon dioxide emissions.