Introduction: The trend in state motorcycle helmet laws has been a reduction from universal coverage requiring all riders to wear helmets, to partial coverage requiring only younger riders to wear helmets. In the current study we evaluate whether partial helmet laws reduce motorcycle fatalities and increase helmet compliance among young riders.
Materials and Methods: We compared a decade of motorcycle fatalities from the only 3 states with no helmet laws (New Hampshire, Iowa, Illinois) to 3 states with ≤17-year-old partial helmet laws (Connecticut, Indiana, Wisconsin). We excluded highway speeds, blood alcohol laws, and minimum legal drinking age as being significant variables.
Results: Overall, there was no significant difference in the average fatality rate per 10,000 motorcycle registrations for ≤17-year-old riders in partial helmet law states versus no helmet law states (P = 0.45). Furthermore, there was no significant difference in the helmet wearing rate of ≤17-year-old fatalities in partial helmet law versus no helmet law states (P = 0.79).
Conclusions: Partial helmet laws neither significantly reduce fatality rates nor increase helmet compliance rates among young riders. A partial helmet law is roughly equivalent to none at all; only universal helmet laws have been shown to effectively protect young motorcyclists.