Bike sharing is taking off in major cities as an environmentally friendly, health-conscious transport alternative. But like anything, bike sharing isn’t perfect. One imperfection: it's much easier to create a system of communal bikes than a system of communal helmets.
Across a number of cities that have instituted bike-sharing programs, though, head injuries have gone up in proportion to other bicycle-related injuries, a study published last week indicated.
The study looked at five cities that had bike-sharing (Montreal, Miami Beach, Boston, Washington, D.C., and Minneapolis) and five that didn’t. The researchers found that in cities with bike-share programs, the proportion of bicycle-related head injuries that led to admission to a trauma center increased by 14 percent.
"The study basically confirmed our worries," says Janessa Graves, who works on pediatric injury prevention at Washington State University's nursing school in Spokane. She's the lead author of the study, published online Thursday by the American Journal of Public Health. "Public bike-share initiatives are great wellness initiatives," she tells Shots. "But without providing helmets, we were concerned that we would see an increase in head injuries. And we did."
But, as the Atlantic's City Lab pointed out, there are other ways to interpret the results. Kay Teschke, a professor who studies cycling in cities at the University of British Columbia, took a look at the data and found that while, yes, the proportion of head injuries to other injuries went up in cities with bike share programs, "the total number of injuries went down, and the number of head injuries went down." City Lab:
The AJPH paper failed to mention the second and arguably more crucial point. So rather than conclude that bike-share systems might be increasing rider safety, the researchers argued that bike-share systems might improve head safety by offering helmets. In that sense, they seemed to miss the forest for the trees.
"It seems critical to me, especially for people interested in bike-share, to report that injuries overall went down, including head injuries," says Teschke. "That's really important. Especially because it is likely that cycling went up in those cities."
Promoting helmet use might seem like a no-brainer. But helmet laws are a flashpoint in an ongoing battle about bike infrastructure and bike laws. "Proponents of helmet laws say that they reduce injuries. But evidence for this claim remains mixed," the Washington Post wrote last year. Counterintuitively, bike advocates often fight against mandatory helmet laws because they discourage people from getting on a bike to begin with—and one of the clear way to reduce injuries is getting more cyclists on the road. This camp might point to NYC's helmet-less bike-share program as a good example of why helmets aren't necessary: one year in, no cyclist has died on a Citi Bike, and only 25 trips (out of 8,750,000) ended in the ER.
On the other hand, helmets are still important safety gear, and if you're planning on getting on a bike, it's a good idea to wear one. The authors of the new study concluded that more efforts should be made to incorporate helmets into bike sharing programs, even at the planning stages. Giving people the option of wearing a helmet is a good idea. But so is encouraging more people to bike, which means being clear that bike-shares are not leading to more head injuries.