Analysis of Motorcycle Crashes: Comparison of 2012 to Previous Years Carol A. Flannagan, Ph.D. Center for the Management of Information for Safe and Sustainable Transportation (CMISST) Biosciences Group, UMTRI

Motorcycle Crashes The motorcycle helmet law was modified as of April 13, 2012 What was the picture of motorcycle crashes in 2012 and how did they change (or not) compared to previous years?

Annual Numbers Annual motorcycle crashes: YearTotal Crashes

Annual Numbers Occupants of motorcycles in crashes: YearTotal People

Who is involved in motorcycle crashes?

Who is involved in motorcycle crashes? 2012

What About Helmet Use? Time PeriodYear(s) Helmet Use Rate in Crashes Jan 1-Apr % % Apr 13-Dec % % *74% is probably an underestimate of the true helmet use rate on the road

Fatalities and Injuries Apr 13-Dec 31 Year(s) Helmet Use Fatalities (per year) Serious Injuries (per year) Percent Fatal Percent Serious Injury 2011 Yes %19% No6237.2%31% 2012 Yes %16% No %23%

Fatalities and Injuries Apr 13-Dec 31 Overall fatality rate in 2011 = 3.3% Overall fatality rate for 2012 = 3.4% Fatality rate was 2.8 times higher for those who didn’t wear helmets in 2012 compared to those who did

Who Wears Helmets? RoleYear(s)Helmet Rate Driver % % Passenger % %

Who Wears Helmets? GenderYear(s)Helmet Rate Male % % Female % %

Who Wears Helmets? Driver DrinkingYear(s) Helmet Use Rate Driver Not Drinking % % Driver Drinking % %

Who Wears Helmets? CategoryYear(s) Percent Riders with Drinking Driver Helmet % % No Helmet % %

How Does Fatality Risk Change with Alcohol and Helmet Use? Helmet UseAlcohol UseYearPercent Killed Helmet Worn Driver Drinking % % Driver Not Drinking % % No Helmet Worn Driver Drinking % % Driver Not Drinking % %

Separating the Effect of Alcohol from the Effect of the Helmet How do we figure out what the helmet does separate from risk-taking factors like alcohol use? Regression models allow us to predict risk of fatality or injury account for alcohol, speed, age, and other factors

Bottom Line… Taking risk-taking factors into account, we find: Alcohol more than quadruples the risk of death and nearly triples the risk of serious injury After accounting for other risk factors, not wearing a helmet doubles the risk of fatality and increases the risk of serious injury by 60%

Bottom Line… If we apply the models to 2012 data and predict what would have happened if all riders had worn helmets, we would expect: 26 fewer deaths (21% reduction) 49 fewer serious injuries (8% reduction)

Thanks for your attention. University of Michigan Transportation Research Institute (UMTRI)