Bicycle Helmet Laws

IMPACT:

LOCUS:

ORIGIN: Cochrane Collaboration and peer-reviewed systematic reviews

Publication Date: 12/07/2009

Author(s): NPO Staff

The Problem:

As of 1995, bicycle crashes caused approximately 1,000 deaths and 550,000 emergency room visits per year. The majority of these injuries involve some form of head trauma. CDC. Injury-Control Recommendations: Bicycle Helmets.  MMWR. 1995;44(RR-1):1-18.

 

The Law:

Many states and localities have responded to bicycle-related morbidity and mortality by mandating helmet use by bicyclists. Some states mandate helmets for all bicyclists under a certain age; 15 is a common threshold (NC GS 20.171.7, North Carolina). States enforce bicycle helmet laws with fines (e.g., California, Cal Veh Code § 21212) or by impounding the violators’ bikes (e.g., Georgia, O.C.G.A. § 40-6-296(e)(1)). For other examples of helmet laws, see Fla. Stat. § 316.2065(3)(d) (Florida) and MD Transportation Code § 21-1207.1 (Maryland).

The Evidence:

Two groups of researchers have systematically reviewed studies evaluating the impact of bicycle helmet laws. Macpherson and Spinks reviewed five studies that measure the effectiveness of bicycle helmet laws as a public health intervention aimed at reducing head injuries. Macpherson A, Spinks A. Bicycle Helmet legislation for the uptake of helmet use and prevention of head injuries. Evidence-Based Child Health: A Cochrane Review Journal. 2008;3:16-32. Of the five studies, two measured the effect of such laws on the rate of helmet use and two measured the impact of the laws on bicycle related head injuries; the fifth study measured both outcomes. Based on statistically significant increases in helmet use and decreases in bicycle-related head injuries, the authors conclude bicycle helmet laws are an effective public health intervention. Karkhaneh et al. reviewed a broader sample of twelve studies assessing the effectiveness of bicycle helmet laws in increasing helmet use. Karkhaneh M, Kalenga J-C, Hager BE, Rowe BH.  Effectiveness of bicycle helmet legislation to increase helmet use: a systematic review. Injury Prevention. 2006;12(2):76-82. Across the twelve studies, seven found increases of helmet use that were greater than 30%, four found increases between 10% and 30% and one found an increase of 5%. According to the authors, the studies collectively support the effectiveness of bicycle helmet laws. 

The Bottom Line:

In the judgments of the authors of a Cochrane Collaboration systematic review and the authors of a peer-reviewed systematic review, bicycle helmet laws are an effective public health intervention aimed at reducing head-related morbidity and mortality.

Additional Information:

The Insurance Institute for Highway Safety, Highway Loss Data Institute provides online access to a table of state laws requiring bicycle helmet use.

Additional Resources: Insurance Institute for Highway Safety, Highway Loss Data Institute

Categories:

What are Evidence Briefs?

A Public Health Law Research Program “Evidence Brief” summarizes the research assessing the effect of a specific law or policy on public health. 

Evidence Briefs are prepared by the staff of the National Program Office. Briefs are based on systematic literature reviews conducted by highly-regarded scholars and published by credible organizations or peer-reviewed journals. Evidence Briefs digest the best available evidence, but readers should bear in mind that even the best evidence may have limitations or deficiencies. 

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