Bicycle Lies, Damned Lies, and Statistics

Mark Twain is well known for the saying “There are three kinds of lies: lies, damned lies, and statistics.” After years of environmental law practice, an area rife with “advocacy science,” it is my opinion that all statistics are true, depending what they describe, how the data was gathered, and its relevance. Getting this information often requires looking past the number, which on its own can be misleading and checking the references.

The Governors Highway Safety Association recently made headlines with statistics when it released a report concluding that “Bicyclist Fatalities a Growing Problem for Key Groups” (you find the full report here). The key findings were –

  • The most bicyclists killed from 2010 through 2012 were in California, Florida, Texas, New York, and Illinois (in that order).
  • The number of bicyclists killed in motor vehicle crashes between 2010 and 2012 was up 16 percent, from 621 deaths to 722.
  • Adult males are almost 3/4 of those bicyclists killed, whereas before most bicyclists killed were children.
  • Adults are most likely to die in bicyclist fatalities.
  • More than 2/3 of bicyclists fatally injured in 2012 weren’t wearing helmets.
  • More than 1/4 of adult bicyclists who were killed in 2012 were alcohol impaired.

News reporting the results of the study led with sensationalist headlines emphasizing the soaring number of bicycling fatalities and California’s nationwide lead among bicycling fatalities. While the GHSA begins its report with the caveat that data for important information about ridership, number of miles ridden, where people ride, etc. is lacking or nonexistent, you had to read the report to get any of this. If you relied on the news stories you got a sentence or two, if anything.

Part of the problem (and I hate to sound like Fox News) is the media itself, which tends to lead with sensationalist headline and often has word limits too restrictive to sufficiently discuss nuanced issues. Some of the news commentary got into the nuances and implications of the GHSA report (Report on bike deaths misses chance to focus on real problems (Sacramento Bee)  There’s Been A Rise In Bike Fatalities, But That’s Not The Whole Story (Huffington Post)). Unfortunately, this didn’t happen until a couple days after the major headlines and, but then, most people probably didn’t notice (if they every noticed in the first place).

Despite the data limitations described by the GHSA, there nonetheless seems to be enough information to conclude that the increase in cycling fatalities is likely due to more people cycling (as opposed to increased risk). Although California led the way in fatalities, California is also has more people than any other state and its climate makes bicycling feasible year-round, despite its car-centric culture. Alcohol played a role in many bicycling fatalities, but since alcohol was associated with fewer bicycling fatalities than motor vehicle fatalities, the could more be a problem with drinking behavior generally than with bicycling.

While the GHSA and the news focused a lot on helmet use, the shift in fatalities from rural to urban areas could be more important. If the shift occurred due to more riding in urban areas, it means more bicyclists are exposed to conflicts with pedestrians and motor vehicles in urban areas. Helmets remain important, but cities need to address infrastructure like protected bike lanes and better street design. As stated in the report, “Roads were built to accommodate motor vehicles with little concern for pedestrians and bicyclists.” (GHSA Report, p. 13.) The GHSA recommends protected bike lanes as the ideal solution and, where protected bike lanes are not feasible, reducing the distance or time in which bicyclists are exposed to risk, using infrastructure features such as marked bike lanes (i.e. Class 2 Bike Lanes), bicycle boulevards, bike boxes, and separate bicycle traffic signals. Local governments can also use traffic calming measures to slow down traffic.

Of all of the GHSA’s conclusions, its most important was “Increasing safety of bicyclists on road is key to increasing use of bikes.” Unfortunately, this this conclusion never appeared in the news articles (at least not the ones I read through) or in any of the headlines. We, as consumers, voters, and members of the public get a lot of statistics and conclusions from reports. In order to develop our own informed opinions, however, we need to look beyond the headline and often even the news story.

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