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?
FatalInjury(K)
SuspectedSerious Injury (A)
SuspectedMinor Injury (B)
PossibleInjury(C)
NoApparentInjury
(O)

3. Annual Numbers Annual motorcycle crashes: Year Total Crashes 2008 3969
2009
3338
2010
3285
2011
3104
2012
3510
FatalInjury(K)
SuspectedSerious Injury (A)
SuspectedMinor Injury (B)
PossibleInjury(C)
NoApparentInjury
(O)

4. Annual Numbers Occupants of motorcycles in crashes: Year Total People
2008
4493
2009
3812
2010
3741
2011
3509
2012
3948
FatalInjury(K)
SuspectedSerious Injury (A)
SuspectedMinor Injury (B)
PossibleInjury(C)
NoApparentInjury
(O)

5. Who is involved in motorcycle crashes?
FatalInjury(K)
SuspectedSerious Injury (A)
SuspectedMinor Injury (B)
PossibleInjury(C)
NoApparentInjury
(O)

6. Who is involved in motorcycle crashes?
2012
FatalInjury(K)
SuspectedSerious Injury (A)
SuspectedMinor Injury (B)
PossibleInjury(C)
NoApparentInjury
(O)

7. Helmet Use Rate in Crashes
What About Helmet Use?
Time Period
Year(s)
Helmet Use Rate in Crashes
Jan 1-Apr 12
97%
2012
96%
Apr 13-Dec 31
98%
74%
FatalInjury(K)
SuspectedSerious Injury (A)
SuspectedMinor Injury (B)
PossibleInjury(C)
NoApparentInjury
(O)
*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
Yes 97
574
3.2%
19% No 6 23
7.2%
31%
2012 56
390
2.3%
16% 55
194
6.5%
23%
FatalInjury(K)
SuspectedSerious Injury (A)
SuspectedMinor Injury (B)
PossibleInjury(C)
NoApparentInjury
(O)

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 compared to those who did
FatalInjury(K)
SuspectedSerious Injury (A)
SuspectedMinor Injury (B)
PossibleInjury(C)
NoApparentInjury
(O)

10. Who Wears Helmets? Role Year(s) Helmet Rate Driver 2008-11 98% 2012
74%
Passenger
97%
75%
FatalInjury(K)
SuspectedSerious Injury (A)
SuspectedMinor Injury (B)
PossibleInjury(C)
NoApparentInjury
(O)

11. Who Wears Helmets? Gender Year(s) Helmet Rate Male 2008-11 98% 2012
73%
Female
97%
78%
FatalInjury(K)
SuspectedSerious Injury (A)
SuspectedMinor Injury (B)
PossibleInjury(C)
NoApparentInjury
(O)

12. Who Wears Helmets? Driver Drinking Year(s) Helmet Use Rate
Driver Not Drinking
98%
2012
76%
90%
54%
FatalInjury(K)
SuspectedSerious Injury (A)
SuspectedMinor Injury (B)
PossibleInjury(C)
NoApparentInjury
(O)

13. Percent Riders with Drinking Driver
Who Wears Helmets?
Category
Year(s)
Percent Riders with Drinking Driver
Helmet
7.1%
2012
5.2%
No Helmet
30%
13%
FatalInjury(K)
SuspectedSerious Injury (A)
SuspectedMinor Injury (B)
PossibleInjury(C)
NoApparentInjury
(O)

14. How Does Fatality Risk Change with Alcohol and Helmet Use?
Alcohol Use
Year
Percent Killed
Helmet Worn
Driver Drinking
2011
12.3%
2012
11.1%
Driver Not Drinking
2.6%
1.8%
No Helmet Worn
13.0%
14.7%
4.3%
5.3%
FatalInjury(K)
SuspectedSerious Injury (A)
SuspectedMinor Injury (B)
PossibleInjury(C)
NoApparentInjury
(O)

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
FatalInjury(K)
SuspectedSerious Injury (A)
SuspectedMinor Injury (B)
PossibleInjury(C)
NoApparentInjury
(O)

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%
FatalInjury(K)
SuspectedSerious Injury (A)
SuspectedMinor Injury (B)
PossibleInjury(C)
NoApparentInjury
(O)

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)