1. 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

2. 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?

3. Annual Numbers Annual motorcycle crashes: YearTotal Crashes 20083969 20093338 20103285 20113104 20123510

4. Annual Numbers Occupants of motorcycles in crashes: YearTotal People 20084493 20093812 20103741 20113509 20123948

5. Who is involved in motorcycle crashes? 2008-2011

6. Who is involved in motorcycle crashes? 2012

7. What About Helmet Use? Time PeriodYear(s) Helmet Use Rate in Crashes Jan 1-Apr 12 2008-201197% 201296% Apr 13-Dec 31 2008-201198% 201274% *74% is probably an underestimate of the true helmet use rate on the road

8. Fatalities and Injuries Apr 13-Dec 31 Year(s) Helmet Use Fatalities (per year) Serious Injuries (per year) Percent Fatal Percent Serious Injury 2011 Yes975743.2%19% No6237.2%31% 2012 Yes563902.3%16% No551946.5%23%

9. 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

10. Who Wears Helmets? RoleYear(s)Helmet Rate Driver 2008-1198% 201274% Passenger 2008-1197% 201275%

11. Who Wears Helmets? GenderYear(s)Helmet Rate Male 2008-1198% 201273% Female 2008-1197% 201278%

12. Who Wears Helmets? Driver DrinkingYear(s) Helmet Use Rate Driver Not Drinking 2008-11 98% 2012 76% Driver Drinking 2008-11 90% 2012 54%

13. Who Wears Helmets? CategoryYear(s) Percent Riders with Drinking Driver Helmet 2008-117.1% 20125.2% No Helmet 2008-1130% 201213%

14. How Does Fatality Risk Change with Alcohol and Helmet Use? Helmet UseAlcohol UseYearPercent Killed Helmet Worn Driver Drinking 201112.3% 201211.1% Driver Not Drinking 20112.6% 20121.8% No Helmet Worn Driver Drinking 201113.0% 201214.7% Driver Not Drinking 20114.3% 20125.3%

15. 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

16. 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%

17. 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)

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