U.S. Department

of Transportation

National Highway

Traffic Safety

Administration

DOT HS 809-715 March 2004

Technical Report

Motorcycle Helmet Effectiveness 

Revisited

National Center for Statistics and Analysis

This publication is distributed by the U.S. Department of Transportation, National Highway Traffic Safety 

Administration, National Center for Statistics and Analysis, in the interest of information exchange. The 

opinions, findings and conclusions expressed in this publication are those of the author(s) and not necessarily 

those of the Department of Transportation or the National Highway Traffic Safety Administration. The United 

States Government assumes no liability for its contents or use thereof. If trade or manufacturers’ names are 

mentioned, it is only because they are considered essential to the object of the publication and should not be 

construed as an endorsement. The United States Government does not endorse products or manufacturers.

Technical Report Documentation Page

1. Report No.

DOT HS 809 715

2. Government Accession No. 3. Recipient’s Catalog No.

5. Report Date

March, 2004

4. Title and Subtitle

Motorcycle Helmet Effectiveness Revisited

6. Performing Organization Code

NPO-101

7. Author(s)

William Deutermann

8. Performing Organization Report No.

9. Performing Organization Name and Address 10. Work Unit No. (TRAIS)n code

Mathematical Analysis Division, National Center for Statistics and 

Analysis

National Highway Traffic Safety Administration

US Department of Transportation

NPO-101, 400 Seventh Street S.W.

Washington, DC 20590

11. Contract of Grant No.

13. Type of Report and Period Covered

NHTSA Technical Report

12. Sponsoring Agency Name and Address

Mathematical Analysis Division, National Center for Statistics and 

Analysis

National Highway Traffic Safety Administration

US Department of Transportation

NPO-121, 400 Seventh Street S.W.

Washington, DC 20590

14. Sponsoring Agency Code

15. Supplementary Notes

16. Abstract

This report looks at the measurement of how effective motorcycle helmets are in preventing fatalities in 

motorcycle crashes. Based on a comparison of crashes involving motorcycles with two occupants, at least 

one of whom was killed, the method uses data from the Fatality Analysis Reporting System (FARS) to 

estimate helmet effectiveness. Technological changes over the past 15 years have led to improvements in 

helmet design and materials. Recalculating the effectiveness of helmets in preventing fatalities, using more 

recent data, shows that helmets have indeed improved in this respect. The effectiveness of helmets has 

increased from 29 percent in 1982 through 1987 to 37 percent over the years 1993 through 2002. The 

significance of this improvement is that over the same period, helmets have saved the lives of 7,808 riders. 

The potential number of lives saved over the period is even higher, at 11,915. Unfortunately, the declining 

rate of helmet use among motorcyclists has contributed to rising numbers of rider fatalities despite the 

improved life saving qualities of helmets.

17. Key Words 

Motorcycle, Helmet, Effectiveness, Fatal crash, 

Helmet laws, Fatality Analysis Reporting System 

(FARS)

18. Distribution Statement

This Document is available to the public through the 

National Technical Information Service, 

Springfield, VA 22161

19. Security Classification (of this report)

 Unclassified

20. Security Cl assification (of this page)

 Unclassified

21. No of Pages

15

22. Price

Form DOT F1700.7 (8-72) Reproduction of completed page authorized

Table of Contents

Executive Summary.................................................................................................................................................1

Highlights.................................................................................................................................................................2

1.0 Introduction......................................................................................................................................................3

2.0 Methodology....................................................................................................................................................5

3.0 Revising Estimated Effectiveness....................................................................................................................9

3.1 Updating The Data .................................................................................................................................. 9

3.2 The Weighted Average Effectiveness................................................................................................... 14

3.0 Conclusions....................................................................................................................................................16

5.0 References......................................................................................................................................................17

 National Center for Statistics and Analysis, 400 Seventh St., S.W., Washington, DC 20590 1

Executive Summary

Using Fatality Analysis Reporting System (FARS) data from 1993 through 2002, this 

report recalculates the “effectiveness ” of helmets in preventing fatalities in motorcycle 

crashes. The resulting effectiveness of 37 percent represents a significant improvement 

over the previous estimate of 29 percent obtained using data from 1982 through 1987. 

The 37 percent effectiveness would mean that from 1993 through 2002 helmets saved 

7,808 lives, a substantial increase compared with the estimate of 5,430 lives saved using 

the old effectiveness measure.

The past fifteen years have seen significant advances in motorcycle helmet design and 

materials. As a result, the newer helmets afford a much greater degree of protection 

against potentially fatal head injuries. 

Based on a comparison of fatal crashes involving motorcycles with two occupants, at 

least one of whom was killed, NCSA calculates the “effectiveness” of helmets in

preventing fatalities. Recalculating the effectiveness of helmets in preventing fatalities 

using more recent data shows that helmets have indeed improved in their ability to 

protect the wearer. Unfortunately, the potential benefits of improved helmets are not 

being realized, as fatalities continue to rise in response to declining helmet usage rates. 

Had all motorcyclists consistently worn proper helmets over the 1993 to 2002 time 

period, the number of lives saved would have been much higher at 11,915.

Despite the fact that less than 3 percent of registered passenger vehicles are motorcycles, 

motorcyclist fatalities represent about nine percent of all passenger vehicle occupant 

fatalities. Considering that passenger car occupant fatalities are trending downward, 

policies that result in raising public acceptance of the protective va lue of helmets can 

have a significant impact on reducing the total number of lives lost annually on

America’s highways.
 

 National Center for Statistics and Analysis, 400 Seventh St., S.W., Washington, DC 20590 2

Highlights

q The state of the art in helmet design and materials has improved significantly over 

the past fifteen years, and their effectiveness in preventing fatalities is greater than 

previous estimates indicated.

q As a result of these improvements, motorcycle helmets are currently estimated to 

be 37 percent effective in preventing rider fatalities, compared with the 1989 

estimated effectiveness of 29 percent.

q The higher effectiveness means that over the ten-year period from 1993 through 

2002, motorcycle helmets have saved 7,808 lives, 2,378 more than was previously 

thought.

q Effectiveness of 37 percent means that a rider can reduce his or her risk of

suffering a fatal injury in a crash by over one-third simply by wearing a proper 

helmet.

q Despite the improved performance of helmets, the incidence of fatal motorcycle 

crashes in the United States has been increasing in recent years, as the percentage 

of riders who use helmets has fallen from 71 percent to 58 percent nationally.
 

 National Center for Statistics and Analysis, 400 Seventh St., S.W., Washington, DC 20590 3

Motorcycle Helmet Effectiveness Revisited

1.0 Introduction

The past fifteen years have seen significant advances in motorcycle helmet design and 

materials. As a result, the newer helmets afford a much greater degree of protection 

against potentially fatal head injuries. Despite these technological improvements,

NHTSA is still using the 29 percent helmet effectiveness calculated from observed 

fatality data from the 1980’s.

This report uses more recent data from the Fatality Analysis Reporting System (FARS) to 

update the estimated protective value of motorcycle helmets in the prevention of fatal 

head injuries and to estimate the total number of lives saved by helmets. An

“effectiveness” of 29 percent means that use of a proper helmet can improve a rider’s 

chances of surviving a potentially fatal crash by almost one-third. The fact that

motorcyclist fatalities represent about nine percent of all passenger vehicle occupant 

deaths, despite the relatively low numbers of motorcycles vis-à-vis other passenger 

vehicles traveling the nation’s highways, underscores the protective value of motorcycle 

helmets.

In terms of lives saved, the 29 percent effectiveness me ans that over the recent ten-year 

period from 1993 through 2002, motorcycle helmets have saved 5,430 lives. This

estimate is conservative, given the known improvements in helmet technology over the 

same period. If effectiveness were recalculated based on more recent mortality data, one 

would expect to see a higher effectiveness and a concomitant increase in the number of 

lives saved.

While helmets have improved, the proportion of riders who actually use them has 

declined. In the United States in 2002, motorcycle crashes claimed the lives of 3,244 

motorcyclists and injured another 65,000. Many of these riders were not wearing

helmets. In fact, the 2002 National Occupant Protection Use Survey (NOPUS) data on 

helmet usage shows that only 58 percent of motorcyclists wear helmets when they ride, a 

sharp drop from the 71 percent usage rate in 2000. With the repeal or watering down of 

helmet laws in many states, both the percentage of non-users and the number of fatalities 

have grown.

Since 1974, motorcycle helmets are required to meet or exceed the Department of

Transportation’s Federal Motor Vehicle Safety Standard (FMVSS) No. 218. In addition, 

many helmet manufacturers voluntarily submit their products for testing and certification 

under the standards deve loped and periodically updated by private testing laboratories. 

In particular, the requirements of FMVSS 218, together with changes in design and 

materials used in manufacturing helmets, are the driving force behind the improved 

effectiveness of helmets. One of the more significant innovations introduced in the early 

1990s has been the use of materials such as Kevlar, expanded polypropylene, and carbon 

fiber in the manufacture of helmet shells and protective linings. 
 

 National Center for Statistics and Analysis, 400 Seventh St., S.W., Washington, DC 20590 4

Of course, head injuries are not the only cause of crash fatalities. When we speak of 

“effectiveness” of helmets in reducing the risk of death in fatal motorcycle crashes, all 

types of injuries suffered by riders are included by implication. For example, if a helmet 

were absolutely certain to prevent a severe head injury, the rider could still die from other 

traumatic injuries suffered in a crash. Clearly, motorcycle helmets cannot prevent all 

fatal injuries, but in the case of head injuries in particular, helmets do provide a measure 

of preventive protection to the wearer. Just how effective helmets are in preventing 

fatalities is a function of both their performance in crashes and the incidence of fatal 

injuries other than head injuries. While it would be useful to know the effectiveness of 

helmets in preventing potentially fatal head injuries alone, the purpose of effectiveness as 

calculated here is to provide a measure of the overall difference in survival value in a 

potentially fatal crash that is attributable to the proper use of a helmet.

A number of studies have shown helmets to be an important factor in preventing death or 

serious injury in motorcycle crashes. Braddock, Schwartz et al. (1992), found that unhelmeted motorcyclists were 3.4 times more likely to die than were helmeted riders. A 

study by Kelly, Sanson et al. (1991) found that injured non-helmeted riders had higher 

injury severity scores and sustained more head and neck injuries. Of the 26 fatally 

injured riders in this study, 25 were un-helmeted. A three year study of helmet use in 

Colorado found that following repeal of a helmet law in 1977, helmet usage declined 

from 99 percent to as low as 49 percent, while the motorcycle fatal crash rate increased 

by more than 100 percent and the injury crash rate increased by 13 percent. More 

recently, a 2003 evaluation of the repeal of helmet laws in Kentucky and Louisiana found 

that in both states, the helmet use rate declined rapidly in the years following repeal, from 

96 percent to 56 percent in Kentucky and from about 100 percent to 52 percent in

Louisiana, while the fatalities increased correspondingly in both states.

In support of revisiting motorcycle helmet effectiveness in saving lives, an analysis of 

data from the Department of Transportation’s Crash Outcome Data Evaluation System 

(CODES) in 1996 showed that “...motorcycle helmets are 35 percent effective in

preventing fatality, 26 percent effective in preventing injuries at least serious enough to 

require transport to the hospital ED [Emergency Department], and 9 percent effective in 

preventing all injury.” 

There is an inescapable irony in all these statistics: On the one hand, real world crash 

experience and destructive testing both suggest that the protective value of helmets has 

improved over the years. On the other hand, NCSA’s studies of helmet use indicate that 

the usage rate is falling as more riders choose not to wear helmets and existing helmet 

laws are repealed or weakened.
 

 National Center for Statistics and Analysis, 400 Seventh St., S.W., Washington, DC 20590 5

2.0 Methodology

In 1989, using Fatality Analysis Reporting System (FARS) data for 1982 through 1987, 

Wilson estimated that motorcycle helmets were 29 percent effective in preventing

occupant fatalities in motorcycle crashes. She based her calculation on a paired

comparison study of crashes resulting in at least one fatality and involving one or more 

motorcycles each of which carried one rider and one passenger. The methodology was 

based on previous work by Evans on the effect of vehicle mass on driver fatalities (1984); 

Kahane (1986) and Partyka (1987, 1988) on the effectiveness of seat belts and other 

restraint systems; and Evans and Frick (1988), on the effectiveness of motorcycle

helmets. Since 1989, NHTSA has used the 29 percent effectiveness to calculate the 

number of lives saved through the use of motorcycle helmets.

Motorcycle crashes with fatal outcomes involving one rider and one passenger were 

compared using a matched pairs procedure. Limiting the crashes to those involving a 

rider and passenger combination gives the following four possibilities:

Table 1. - Rider/Passenger

Helmet Use Combinations

Passenger 

Not Helmeted

Passenger 

Helmeted

Rider Not

Helmeted

Neither rider nor 

passenger 

helmeted

Rider not 

helmeted, 

passenger 

helmeted

Rider

Helmeted

Rider helmeted, 

passenger not 

helmeted

Both rider and 

passenger 

helmeted

For each of the four possible combinations, ratios were calculated for rider to passenger 

fatalities and passenger to rider fatalities in a given year. For example, in those cases in 

which neither the rider nor the passenger used a helmet, the Fatality Ratio (FR) of rider to 

passenger deaths, is:

FR (RNH) =Rider (NH) /Psgr (NH)

And in those cases where only the rider was helmeted, the Fatality Ratio is:

FR(RH) =Rider(H) /Psgr (NH)

The fatality ratios were used to calculate separate helmet effectiveness, expressed as a 

percentage, for riders and passengers. It is assumed that any difference between the 

fatality ratios for unhelmeted and helmeted motorcycle occupants in each of the possible 
 

 National Center for Statistics and Analysis, 400 Seventh St., S.W., Washington, DC 20590 6

scenarios is due to the effectiveness of the helmet. For example, the effectiveness of a 

helmet in preventing fatal injuries to a rider accompanied by an unhelmeted passenger 

would be:

Effectiveness = (FR(RNH) - FR(RH)) / FR(RNH)

Wilson calculated the fatality ratios and effectiveness for each year of the six-year period 

from 1982 through 1987 (Table 2) to show the variation that occurs from year to year as 

the result of the small number of cases in some of the cells. To control for this variation, 

multiple years of data were used to calculate the overall effectiveness for the different 

combinations of riders and passengers. Aggregating data over the 5-year period from 

1982 through 1987 results in an overall 29 percent effectiveness of helmets in preventing 

fatal injuries in otherwise fatal motorcycle crashes (lower right hand cell in Table 3).
 

 National Center for Statistics and Analysis, 400 Seventh St., S.W., Washington, DC 20590 7

Table 2 - Rider/Passenger Fatalities in Motorcycle Crashes*

By Helmet Use Status

1982-1987

Helmet Used No of Deaths Fatality Ratios

Year Rider Passenger Rider Passenger Rider/Psgr Psgr/Rider

No No 297 237 1.253 0.798

No Yes 19 15 1.267 0.789

Yes No 37 44 0.841 1.189

1982

Yes Yes 183 155 1.181 0.847

No No 263 224 1.174 0.852

No Yes 25 12 2.083 0.480

Yes No 24 31 0.774 1.292

1983

Yes Yes 160 131 1.221 0.819

No No 243 232 1.047 0.955

No Yes 21 13 1.615 0.619

Yes No 30 36 0.833 1.200

1984

Yes Yes 147 123 1.195 0.837

No No 265 236 1.123 0.891

No Yes 17 9 1.889 0.529

Yes No 31 36 0.861 1.161

1985

Yes Yes 144 143 1.007 0.993

No No 263 247 1.065 0.939

No Yes 20 12 1.667 0.600

Yes No 26 31 0.839 1.192

1986

Yes Yes 158 125 1.264 0.791

No No 279 251 1.112 0.900

No Yes 20 11 1.818 0.550

Yes No 20 19 1.053 0.950

1987

Yes Yes 125 102 1.225 0.816

No No 1610 1427 1.128 0.886

No Yes 122 72 1.694 0.590

Yes No 168 197 0.853 1.173

Total

Yes Yes 917 779 1.177 0.850

*Crash must involve both a rider and a passenger on the same motorcycle.

Source: National Center for Statistics and Analysis, NHTSA - FARS 1982-1987
 

 National Center for Statistics and Analysis, 400 Seventh St., S.W., Washington, DC 20590 8

Table 3 - Helmet Use Effectiveness (Percent)

For Motorcycle Riders and Passengers

1982 through 1987

Effectiveness

For: Control 1982 1983 1984 1985 1986 1987 AllYears

Unhelmeted Passenger 33 34 20 23 21 05 24

Rider Helmeted Passenger 07 41 26 47 24 33 31

Average 20 38 23 35 26 19 27

Unhelmeted Rider 01 44 35 41 36 39 33

Passenger Helmeted Rider 29 37 30 14 34 14 28

Average 15 40 33 28 35 26 30

Unhelmeted Control 17 39 28 32 29 22 29

Helmeted Control 18 39 28 31 29 23 29

Rider

And

Passenger Average 17 39 28 31 29 23 29

Source: National Center for Statistics and Analysis, NHTSA - FARS 1982-1987
 

 National Center for Statistics and Analysis, 400 Seventh St., S.W., Washington, DC 20590 9

3.0 Revising Estimated Effectiveness

Since 1987 there have been changes in the design and materials used to manufacture 

motorcycle helmets. Has the effectiveness of motorcycle helmets in reducing fatalities 

also changed and, if so, is the effectiveness higher or lower than it was in 1987?

3.1 Updating The Data

Table 4 shows the annual and total fatality ratios recalculated using the ten most recent 

years of FARS data to reflect technological changes since 1987. The ten-year time 

period was selected in order to increase the number of cases available and to control for 

the effects of years with outlying data. As was the case for the 1982 through 1987 data, 

the individual years are shown for comparison purposes only -- the overall totals were 

used to calculate effectiveness.
 

 National Center for Statistics and Analysis, 400 Seventh St., S.W., Washington, DC 20590 10

Table 4 - Rider/Passenger Fatalities in Motorcycle Crashes*

By Helmet Use Status

1993 - 2002

Helmet Used No of Deaths Ratios

Year Rider Psgr Rider Psgr Rider/Psgr Psgr/Rider

No No 110 105 1.048 0.955

No Yes 13 1 13.000 0.077

Yes No 8 12 0.667 1.500

1993

Yes Yes 105 93 1.129 0.886

No No 89 95 0.937 1.067

No Yes 13 3 4.333 0.231

Yes No 8 11 0.727 1.375

1994

Yes Yes 87 100 0.870 1.149

No No 105 95 1.105 0.905

No Yes 12 5 2.400 0.417

Yes No 9 14 0.643 1.556

1995

Yes Yes 104 82 1.268 0.788

No No 95 94 1.011 0.989

No Yes 13 1 13.000 0.077

Yes No 7 9 0.778 1.286

1996

Yes Yes 106 86 1.233 0.811

No No 94 83 1.133 0.883

No Yes 11 5 2.200 0.455

Yes No 9 5 1.800 0.556

1997

Yes Yes 92 78 1.179 0.848

No No 100 97 1.031 0.970

No Yes 11 3 3.667 0.273

Yes No 4 2 2.000 0.500

1998

Yes Yes 100 82 1.220 0.820

No No 107 89 1.202 0.832

No Yes 15 4 3.750 0.267

Yes No 7 9 0.778 1.286

1999

Yes Yes 81 86 0.942 1.062

No No 111 115 0.965 1.036

No Yes 14 12 1.167 0.857

Yes No 7 8 0.875 1.143

2000

Yes Yes 111 97 1.144 0.874
 

 National Center for Statistics and Analysis, 400 Seventh St., S.W., Washington, DC 20590 11

Table 4 - Rider/Passenger Fatalities in Motorcycle Crashes*

By Helmet Use Status

1993 - 2002

Helmet Used No of Deaths Ratios

Year Rider Psgr Rider Psgr Rider/Psgr Psgr/Rider

No No 142 130 1.092 0.915

No Yes 27 17 1.588 0.630

Yes No 8 8 1.000 1.000

2001

Yes Yes 100 82 1.220 0.820

No No 154 124 1.242 0.805

No Yes 12 8 1.500 0.667

Yes No 4 7 0.571 1.750

2002

Yes Yes 105 83 1.265 0.790

No No 1,107 1,027 1.078 0.928

No Yes 141 59 2.390 0.418

Yes No 71 85 0.835 1.197

Total

Yes Yes 991 869 1.140 0.877

Source: National Center for Statistics and Analysis, NHTSA, FARS 1993-2002

* Crash must involve both a rider and a passenger on the same motorcycle.
 

 National Center for Statistics and Analysis, 400 Seventh St., S.W., Washington, DC 20590 12

Table 5 - Helmet Use Effectiveness (Percent)

For Motorcycle Riders and Passengers

1993 through 2002

Effectiveness

For: Control 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 AllYears

Unhelmeted 

Passenger 36 22 42 23 -59 -94 35 09 08 54 23

Helmeted 

Passenger 91 80 47 91 46 67 75 02 23 16 52 Rider

Average 64 51 45 57 -07 -14 55 06 16 35 37

Unhelmeted 

Rider 92 78 54 92 48 72 68 17 31 17 55

Helmeted 

Rider 41 16 49 37 -53 -64 17 24 18 47 27 Passenger

Average 67 47 52 65 -03 04 43 21 25 32 41

Unhelmeted 

Control 64 50 48 58 -06 -11 52 13 20 36 39

Helmeted 

Control 66 48 48 64 -04 02 46 13 21 32 40

Rider

And

Passenger

Average 65 49 48 64 -05 -05 49 13 21 34 39

Source: National Center for Statistics and Analysis, NHTSA - FARS 1993-2002

In Table 5, a motorcycle helmet effectiveness of 39 percent was calculated using the 

cumulative data from 1993 through 2002, compared with the 29 percent calculated with 

data from 1982 through 1987. As in the 1989 report, multiple years of data were used in 

order to control for the small numbers of crashes meeting the criteria in any particular 

year. In the case of riders accompanied by unhelmeted passengers in 1997, for example, 

9 helmeted riders and 5 unhelmeted passengers were killed in fatal crashes involving both 

a rider and a passenger. This may indicate not only that more motorcyclists are wearing 

helmets, but that passengers accompanying riders wearing helmets are more likely to be 

helmeted as well. One problem in using the paired comparison method to estimate 

effectiveness of protective equipment is that survivors may tend to exaggerate their use in 

order to avoid being cited for non-use. In the case of motorcycle helmets, this effect is 

offset both by the high visibility of motorcycle riders in comparison with motor vehicle 

occupants and the fact that only 20 states and the District of Columbia require all riders to 

wear helmets. There are currently 3 states that do not require helmets and 27 states that 

require helmets only for certain classes of riders.
 

 National Center for Statistics and Analysis, 400 Seventh St., S.W., Washington, DC 20590 13

Effectiveness is used to estimate the number of lives saved as follows:

Lives Saved = Fatalities Helmeted * Effectiveness / (1-Effectiveness)

And the potential number of lives saved as:

Potential Lives Saved = (Fatalities Total + Lives Saved Total) * Effectiveness

Tables 5 and 6 show the numbers of lives saved and the potential lives saved in 2002 

using 29 percent effectiveness (Table 6) and effectiveness as derived from more recent 

data (Table 7).

Table 6 – Motorcyclists Saved by Helmets In 2002

Using Un-weighted Average for Total Effectiveness

(Effectiveness Based on 1982-1987 Data)

Motor Fatalities

Cyclists

Effectiveness

(%) Total Helmeted Unhelmeted

Lives

Saved

Potential

Lives

Saved

Riders 27 3,010 1,598 1,412 591 972

Passengers 30 234 95 139 41 83

Total 29 3,244 1,693 1,551 692 1,141

Source: National Center for Statistics and Analysis, NHTSA – FARS 2002

Table 7 – Motorcyclists Saved by Helmets In 2002

Using Un-weighted Average for Total Effectiveness

(Effectiveness Based on 1993-2002 Data)

Motor Fatalities

Cyclists

Effectiveness

(%) Total Helmeted Unhelmeted

Lives

Saved

Potential

Lives

Saved

Riders 37 3,010 1,598 1,412 939 1,461

Passengers 41 234 95 139 66 123

Total 39 3,244 1,693 1,551 1,082 1,687

Source: National Center for Statistics and Analysis, NHTSA – FARS 2002
 

 National Center for Statistics and Analysis, 400 Seventh St., S.W., Washington, DC 20590 14

3.2 The Weighted Average Effectiveness

One problem with the calculation is obvious from the two tables. If one were to apply the 

separate rates for riders and passengers to obtain the numbers of lives saved and sum the 

results, the total lives saved would be less than the figure obtained using the average total 

rate. The overall rate is a straight, un-weighted average of the component rates, and fails 

to account for differences in the numbers of riders and passengers involved. 

The second proposed change is to use the weighted average of the effectiveness rates 

calculated for riders and passengers separately. Weighted average effectiveness was 

obtained by using the effectiveness rates for riders and passengers to calculate Potential 

Lives Saved for each group over the time periods 1982 through 1987 and 1993 through 

2002. The results were summed to obtain Total Potential Lives Saved as shown earlier in 

Table 7. Total Potential Lives Saved was then used to solve for the total or overall 

effectiveness rate, ER, (Tables 8 and 9).

ER Total = Potential Lives Saved Total / (Lives Saved Total + Fatalities Total ) 

For example, in Table 8,

ER Total = 1,055 / (632+3,244)

 = .27

And in Table 9,

ER Total = 1,584 / (1,005+3,244)

 = .37

Table 8 – Motorcyclists Saved by Helmets In 2002

Using Weighted Average for Total Effectiveness

(Effectiveness Based on 1982-1987 Data)

Motor Fatalities

Cyclists

Effectiveness

(%) Total Helmeted Unhelmeted

Lives

Saved

Potential

Lives

Saved

Riders 27 3,010 1,598 1,412 591 972

Passengers 30 234 95 139 41 83

Total 27 3,244 1,693 1,551 632 1,055

Source: National Center for Statistics and Analysis, NHTSA – FARS 2002
 

 National Center for Statistics and Analysis, 400 Seventh St., S.W., Washington, DC 20590 15

Table 9 – Motorcyclists Saved by Helmets In 2002

Using Weighted Average for Total Effectiveness

(Effectiveness Based on 1993-2002 Data)

Motor Fatalities

Cyclists

Effectiveness

(%) Total Helmeted Unhelmeted

Lives

Saved

Potential

Lives

Saved

Riders 37 3,010 1,598 1,412 939 1,461

Passengers 41 234 95 139 66 123

Total 37 3,244 1,693 1,551 1,005 1,584

Source: National Center for Statistics and Analysis, NHTSA – FARS 2002

Table 10 shows the impact of the higher effectiveness of helmets on the number of lives 

saved over the ten-year period from 1993 through 2002.

Table 10 – Motorcyclists Saved by Helmets

1993 through 2002

Fatalities Effectiveness

Total Helmeted Unhelmeted

Lives

Saved

Potential

Lives

Saved

Current 29 24,396 13,294 11,102 5,430 8,650

Revised 37 24,396 13,294 11,102 7,808 11,915

Difference - - - - 2,378 3,265

Source: National Center for Statistics and Analysis, NHTSA – FARS 2002
 

 National Center for Statistics and Analysis, 400 Seventh St., S.W., Washington, DC 20590 16

3.0 Conclusions

Both the design and materials used in manufacturing motorcycle helmets have improved 

throughout the 1990’s, resulting in a significant improvement in their effectiveness in 

protecting against fatal head injuries. Despite the improvement in effectiveness, from 29 

percent to 37 percent, motorcycle fatalities continue to increase as riders choose not to 

take advantage of the protection afforded by helmets. The weakening or repeal of

compulsory helmet use laws in many states has been shown to be associated with a 

dramatic drop in the percentage of motorcyclists who wear helmets.

Using the new, recomputed effectiveness to calculate the number of lives saved over the 

ten-year period from 1993 through 2002 shows that motorcycle helmets have saved 7,808 

lives, 2,378 more than was previously thought. Unfortunately, with the declining use 

rates in some states more riders are dying unnecessarily. If all riders consistently wore 

proper helmets, the number of additional fatalities that could have been prevented over 

the same ten-year period would have raised the total lives saved to 11,915 persons.

Policies directed toward increasing acceptance of helmets as a protective device can have 

a significant impact on reducing our overall traffic fatality count. Motorcycles compose 

less than three percent of all registered passenger vehicles in the United States, but 

motorcyclist fatalities account for nine percent of all passenger vehicle occupant

fatalities. In recent years, passenger car fatalities have been trending downward – the 

annual rise in overall passenger vehicle fatalities is due to fatal motorcycle and light truck 

crashes.

 
 

 National Center for Statistics and Analysis, 400 Seventh St., S.W., Washington, DC 20590 17

5.0 References

1. Braddock, M. Schwartz, R. Lapidus, G. Banco, L and Jacobs, L., 1992. “A 

Population-Based Study of Motorcycle Injury in Connecticut”, Annals of 

Emergency Medicine, 21(3), 273-278.

2. Evans, Leonard. “Driver Fatalities vs. Car Mass Using a New Exposure 

Approach: Accident Analysis and Prevention”, U.S. Department of 

Transportation, National Highway Traffic Safety Administration, Volume 16, 

Number 1, 1984.

3. Evans, Leonard and Frick, Michael. “Helmet Effectiveness in Preventing 

Motorcycle Driver and Passenger Fatalities: Accident Analysis and Prevention”, 

U.S. Department of Transportation, National Highway Traffic Safety 

Administration, Volume 20, Number 6, 1988.

4. Kahane, Charles. “An Evaluation of Child Passenger Safety: The Effectiveness 

and Benefits of Safety Belts”, U.S. Department of Transportation, National 

Highway Traffic Safety Administration, DOT HS 806 890, February 1986.

5. Kelly, P. Sanson, T. Strange, G. and Orsay, E. “A Prospective Study of the Impact 

of Helmet Usage on Motorcycle Trauma”, Annals of Emergency Medicine, 20 

(8), 852-856, 1991.

6. Krane, S.W. and Winterfield, L. A. “Impact of Motorcycle Helmet Usage in 

Colorado: A Three Year Study, Executive Summary”, DOT HS-805 627, US 

Department of Transportation, National Highway Traffic Safety Administration, 

July 1980.

7. Partyka, Susan. “Papers on Adult Seat Belt Effectiveness and Use”, U.S. 

Department of Transportation, National Highway Traffic Safety Administration, 

DOT HS 807 285, June 1988.

8. Partyka, Susan. “Lives Saved by Child Restraints from 1982 through 1987”, U.S. 

Department of Transportation, National Highway Traffic Safety Administration, 

December 1988.

9. “Report to Congress: Benefits of Safety Belts and Motorcycle Helmets”, DOT HS 

808 347, U.S. Department of Transportation, National Highway Traffic Safety 

Administration, February 1996.

10. Ulmer, R.G. and Preusser, D.F. “Evaluation of the Repeal of Motorcycle Helmet

Laws in Kentucky and Louisiana”, DOT HS 809 530, U.S. Department of 

Transportation, National Highway Traffic Safety Administration, Office of 

Research and Traffic Records, October, 2003.
 

 National Center for Statistics and Analysis, 400 Seventh St., S.W., Washington, DC 20590 18

11. Wilson, Donna C. “The Effectiveness of Motorcycle Helmets in Preventing 

Fatalities”, U.S. Department of Transportation, National Highway Traffic Safety 

Administration, DOT HS 807 416, March 1989.

12. Cover illustration courtesy of “Motorcycle Tips and Techniques”, James R. Davis 

at http://www.msgroup.org/DISCUSS.asp