JAMA (The Journal of the American Medical Association) is one of the world’s preeminent, peer-reviewed medical science periodicals. A study by Harborview Injury Prevention and Research Center, in Seattle, Washington, looked at the “Effectiveness of bicycle safety helmets in preventing head injuries.” JAMA published the work of D. C. Thompson, F. P. Rivara and R. S. Thompson ( dct@u.washington.edu)

Their objective was to examine the protective effectiveness of bicycle helmets in 4 different age groups of bicyclists, in crashes involving motor vehicles, and by helmet type and certification standards. The case subjects were all bicyclists treated in Emergency Departments for head injuries, all who were hospitalized, and all who died at the scene. Control subjects were bicyclists treated for nonhead injuries. There were 3390 injured bicyclists in the study; 29% of cases and 56% of controls were helmeted. Risk of head injury in helmeted vs unhelmeted cyclists adjusted for age and motor vehicle involvement indicate a protective effect of 69% to 74% for helmets for 3 different categories of head injury: any head injury , brain injury, or severe brain injury. The researchers also found similar levels of helmet protection by age. Helmets were equally effective in crashes involving motor vehicles and those not involving motor vehicles .

The investigator’s conclusions: Bicycle helmets, regardless of type, provide substantial protection against head injuries for cyclists of all ages involved in crashes, including crashes involving motor vehicles.