CLAS Undergraduate Research Project

2. Public Bicycle Share Programs and Their
Relevance to Cyclist-Involved Injuries
Tyler Rosen, *Suzanne Baker, PhD, MPH
Department of Public Health; College of Liberal Arts & Sciences

3. ❖ Public bicycle sharing programs (PBSPs) are relatively new in the context of city infrastructure,
with their inception first beginning in the early 90s.
❖ Their use has expanded rapidly in recent years, and are now used in >850 cities across the
world, including right here in Detroit.
❖ This has yielded questions regarding their impact on cyclist safety and, to produce a
competent assessment on the matter, data was compiled from 10 peer-reviewed studies
published no earlier than 2004.
❖ These articles examined rates of cyclist-involved injury both before and after the
implementation of PBSPs, and their data were compared in order to both identify trends and
quantify their impact on cyclist safety.
❖ With one notable exception further expanded upon later, general trends overwhelmingly
pointed towards an increase in cyclist safety with the introduction of public bicycle share
programs.
❖ Ultimately, the evidence pointed out by these trends is strong that public bicycle share
programs (PBSPs) in conjunction with other cyclist infrastructure such as bike lanes, and
appropriate use of helmets, appears to impart a positive impact on health to users, alongside
reducing rates of cyclist-involved injury.
❖ Additionally, a less significant but still measurable positive impact on the environment via
reduced carbon emissions was noted in one study; however, the many environmental factors
present in the duration of the study made suggesting a causal link between the two
problematic.
Abstract

4. Introduction
● Public Bicycle Share Programs (PBSPs) are relatively new from the
standpoint of city infrastructure, having only been developed in the
90s. They present promising potential in terms of positive health
benefits of users; however, as with any new infrastructure, there are
concerns regarding their overall impacts on user safety.
● PBSP implementation has expanded widely since their inception 30
years ago, and now exist in 850+ cities across the world. Many cities
have embraced their presence, facilitating a higher number of cyclists
sharing the road with motor vehicles.
● This new influx of cyclists presents a potential challenge which, over
the past 30 years, has seen an evolution in terms of how cities have
handled the situation. The question this study seeks to answer, given
this context is as such: How has the implementation of these Public
Bicycle Sharing Stations impacted the incidence of cyclist-related
injuries?

5. Methodology/Experimental
A literature review was conducted from analysis of a total 10 peer-reviewed articles.
Articles were screened based on relevancy of data and premise. Articles were sourced
from the following databases: PubMed, MEDLINE, ScienceDirect, ClinicalKey, BMC,
AJPH, and BMJ.
➢ Keywords and phrases: “PBSP”, “injury”, “public bicycle share”, “outcomes”,
“hospital”, and “cycling infrastructure”.
➢ Inclusion criteria, aside from relevancy of premise, were articles published no
earlier than 2004.
➢ Research subjects were users of PBSPs and users of private bicycles (in cases of
comparative research). Subjects were not otherwise limited by demographic,
socioeconomic status, or by other categorical denominations.
➢ Articles which sought to measure correlative before-and-after impacts of Public
Bicycle Sharing Program implementation on cyclist safety and rate of injury were
preferred, as these would best serve to most directly highlight the changes to
cyclist-involved incidents before and after PBSP implementation.

6. Results and Discussion
● Across cities as diverse as Boston, Barcelona, London, Seattle and more, trends
held strong that cyclist safety improved after public bicycle share programs were
implemented.
➢ This occurred either via reduced rate of cyclist-involved injury, or, an increase
in the number of cyclists without any increase in the amount of injuries
reported.
● One study notably found an increase in the number of head injuries in cities which
implemented PBSPs, compared to cities which did not. The author contributed this
to a failure to provide helmets at public bicycle sharing stations. The author also felt
that the absence of proper education or warnings about the dangers of electing not
to use a helmet likely also contributed to these findings.
● Interestingly, one study found a significant environmental benefit after implementing
a public bicycle share program. A study conducted in Barcelona, which examined
the risks vs benefits of PBSP implementation, found that in subsequent years after
PBSP implementation, there were approximately 10 million (9,062,344) less kg in
carbon emissions on a per year basis.

7. Results and Discussion
This graph is a representation of the changes in various events and factors before and
after a public bicycle share was implemented in Barcelona, Spain.

8. Results and Discussion
Below is a visual depiction of a Boston-based study which demonstrated the increase in
cyclists (male, female, and total) per year after a public bicycle sharing station was
implemented.

9. This graph demonstrates the number of injuries/year before and after public bicycle
share implementation in multiple cities. Cities which implemented a PBSP, represented
by the solid line, saw a steady decline post-implementation. This is in contrast to control
cities without PBSPs, which actually saw a slight increase in cyclist-involved injuries.
Results and Discussion

10. Conclusions
➔ Cycling is an activity with links to positive long term health effects and
reductions in risks of developing chronic illnesses such as diabetes, heart
disease, and stroke.
➔ Implementing public bicycle share stations is a good way to promote safe
bicycle use, particularly in the presence of city infrastructure such as bicycle
lanes. Helmet use is a necessity, as an absence of such may actually lead
to an increase in the number of head injuries. Otherwise, the evidence
points to PBSP implementation increasing safety for cyclists for every year
they are implemented.
➔ To summate, the data underlying the topic suggests that PBSPs increase
cyclist safety, physical activity, and may promote miniscule environmental
benefits in the form of reduced carbon emissions. The data is clearer about
health benefits for men than for women and young children, but still
suggests positive health benefits and indicates inclination toward safer
cycling environments for all.

11. Acknowledgments
I wish to give special thanks to Dr. Suzanne Baker, who granted her expertise in
overseeing and guiding my efforts in conducting this study. I also cannot understate my
gratitude to the Public Health program of the College of Liberal Arts & Sciences department
here at Wayne State University. My years in the program equipped me with the means to
complete my own study beginning to end, which is no small feat. The analytical and
methodological approaches I learned in combination with the experience and wisdom of my
many professors in the public health department has been invaluable.
Special thanks to Professor Eduardo Piquieras, who’s methodology class and approach to
teaching the subject matter has proven impeccably useful in the conduction of both this
study and others.