|Preventing Injuries Transportation Injuries|
Public Health Burden
Transportation-related injuries occur from travel on the ground, in the air, and on water. The overwhelming majority of these deaths and injuries result from motor vehicle ground transportation. In 1999, motor vehicle traffic crashes resulted in 40,965 deaths and were the leading cause of death in the United States among people ages 1 to 34. Each year, an additional 3.5 million people suffer nonfatal motor vehicle–related injuries, causing about 4 million emergency department visits and 500,000 hospitalizations. The economic impact is substantial. In 1994, motor vehicle crashes cost more than $150 billion in property damage, lost productivity, and medical expenses. These estimates do not include the unquantifiable costs of pain and suffering or the value of lives lost.
such as increased safety belt use and declining numbers of crashes
involving alcohol, injuries and fatalities caused by motor vehicle crashes
remain a serious public health problem. Data reveal the need to direct
prevention efforts to specific groups, such as older adults, teens, and
children. Pedestrian fatalities are a growing problem, and alcohol
persists as a factor in many crashes and injuries. Collaboration among
many partners is essential to prevent a wide array of
The Injury Center’s Niche in Transportation Safety
CDC’s Injury Center conducts and sponsors population-based epidemiologic, public health, behavioral, biomechanic, and trauma research to develop practical, community-based prevention strategies for motor vehicle–related injuries. CDC has been instrumental in framing motor vehicle injury as a public health problem and in helping to raise public awareness that these injuries are predictable and preventable.
The Injury Center’s research programs focus on determining the magnitude, severity, and cost of motor vehicle injuries; the size and vulnerability of populations at risk; the influence of co-existing medical conditions on crashes and injuries; and causes, risk factors, and effective interventions applicable to public health settings. It is unique in its use of hospitals and emergency departments to collect motor vehicle injury data and to conduct brief interventions. The Injury Center’s peer-review process to select and fund research also distinguishes its work and advances the field; grantees publish their findings in peer-reviewed literature, accelerating the accessibility of knowledge for scientists and public health practitioners. Seven of the 11 CDC-funded university Injury Control Research Centers conduct research about transportation-related injury issues.
The Injury Center’s research priorities in transportation safety build on CDC’s expertise. The focus on alcohol as a risk factor draws on long-standing efforts to document the effects of alcohol on health and safety. Ongoing research includes behavioral risk factor surveillance of alcohol and driving and the identification of risk and protective factors. An emphasis on older drivers reflects CDC’s focus on "healthy aging." Similarly, the Injury Center’s focus on teen drivers takes advantage of CDC’s expertise in quantifying and understanding adolescent health risks. For example, CDC’s Youth Risk Behavior Survey tracks motor vehicle injury risk behaviors among teenagers. The Injury Center takes a developmental-risk perspective on teen drivers, which is characterized by its cooperative research with the National Institutes of Health (NIH) to study the effects of persuasive communication and parental behavior on teen driving behavior. The Injury Center also focuses attention on high-risk, hard-to-reach populations with projects such as Niños Atrás (Kids in the Back), which encourages adults to place children in the back seats of motor vehicles, the safest place for children to ride. And it emphasizes evaluation of community-based interventions. Its research in this area provided the science base for The Guide to Community Preventive Services (produced by the Task Force for Community Preventive Services), which recommends strategies to reduce alcohol-impaired driving and to increase use of safety belts and child safety seats.
The Injury Center works closely with other federal agencies, nonprofit organizations, and researchers. For example, it has a strong partnership with the National Highway Traffic Safety Administration (NHTSA), the lead regulatory agency for motor vehicle safety. The Injury Center’s efforts complement those of NHTSA, which sponsors and conducts research and produces technical reports aimed at supporting traffic safety regulations, motor vehicle safety standards, and legislative initiatives. With NHTSA, the Injury Center hosted the first international conference about preventing childhood pedestrian injuries and widely disseminated national strategies for child pedestrian safety to transportation and public health researchers and policy makers. In partnership with the World Health Organization, the Injury Center developed surveillance guidelines and recommended strategies for motor vehicle injury prevention in developing countries. Injury Center staff also participate on Transportation Research Board committees on transportation for an aging society, alcohol-impaired driving, pedestrian safety, and school bus safety. Other key partners in transportation safety include NIH’s National Institute for Child Health and Human Development, the National Transportation Safety Board, the Insurance Institute for Highway Safety, the AAA Foundation for Traffic Safety, the National SAFE KIDS Campaign, and the National Safety Council.
State and local health
departments are a natural constituency for the Injury Center’s research,
and they provide important entries to develop and implement effective
interventions in communities. CDC’s long history and close relationships
with all 50 state health departments, local health jurisdictions, and
schools of public health provide a foundation from which the Injury Center
can support effective collaborations to prevent transportation-related
The Injury Center’s Priorities in Transportation Safety
Every research priority in this agenda is important. After considering input from experts in the field, Injury Center staff identified the six most important priorities, those that warrant the greatest attention and intramural and extramural resources from the Injury Center over the next three to five years. They are designated with asterisks.
A.* Evaluate strategies to implement and disseminate known, effective interventions to reduce alcohol-impaired driving and test the effectiveness of new, innovative strategies.
Driving after drinking alcohol is a major risk factor for motor vehicle crashes and is associated with approximately 15,000 deaths and 300,000 injuries annually. In 2000, alcohol-related fatality rates increased for the first time in several years, accounting for almost 40% of motor vehicle deaths. For motorcyclists, the rate of alcohol involvement in fatal crashes is even higher. Children are frequent victims of alcohol-impaired drivers. Annually, about 600 children under age 15 die in motor vehicle crashes while riding with drivers who are impaired by alcohol. In addition to the human costs, crashes involving alcohol are expensive. In 1997, these crashes cost Americans $29 billion in direct costs and lost earnings. Law enforcement sources report about 1.4 million arrests for drinking under the influence (DUI) every year, but there are more than 126 million self-reported episodes of DUI.
Since 1970, states and communities have implemented an array of strategies to reduce alcohol-impaired driving. Laws and enforcement strategies to deter alcohol-impaired driving and to control the sale or public consumption of alcohol are among the most widely used strategies. Community-based interventions including sobriety checkpoints, lower legal limits for blood-alcohol content, zero tolerance laws, enhanced enforcement of alcohol control policies, and training programs for servers of alcoholic beverages have been demonstrated effective. However, a better understanding of the factors that most influence successful implementation of these prevention strategies and policies is needed. Research should include strategies drawn from health communication, policy development, advocacy, and other approaches relevant to improving dissemination and adoption of effective interventions.
Research should assess existing interventions directed to high-risk groups and implemented in special settings; screening and early intervention for alcohol-impaired driving in public settings; licensing requirements; and the benefits, costs, and social acceptability of successively lower blood-alcohol concentration standards. Simultaneously, the search for new and innovative strategies for reducing alcohol-impaired driving should continue.
B.* Develop methodologies for and evaluate the effectiveness of various means to translate transportation safety research findings into public policy.
Laws have been applied at both state and federal levels to prevent motor vehicle injuries. However, few tools exist to measure how research translates into laws and regulations to encourage people to adopt safety behaviors. Research about the evolution of prevention strategies—from scientific evidence to legislation to product design and manufacturing changes—has the potential to reduce injury rates on a large scale. For example, research might evaluate the role of tort litigation in providing incentives for industry to make safer products, whether through design modifications or changes in product use. Successful examples include restraint systems, such as safety belts, child safety seats, and vehicle air bags. Research might also evaluate the types of information used to support successful policies and regulatory decisions. For instance, to determine the components of successful campaigns, evaluations could consider the persuasiveness of data about injury’s incidence, prevalence, and outcomes (e.g., disabilities and functional impairments) or the persuasiveness of cost and cost-effectiveness data.
Research should focus on the use of scientific information in formulating public policy that promotes sustainable social changes, on the costs and benefits of changes, and on improvements in public safety. The research should identify best practices for providing useful information to policy makers. Improved social marketing techniques are essential to educate opinion leaders and the public about the causes of motor vehicle–related injuries and about effective personal safety practices.
C.* Evaluate the effectiveness of behavioral and environmental strategies to prevent pedestrian injury.
Pedestrians account for about 14% of motor vehicle–related deaths in the U.S. Most pedestrians injured or killed are young children, older adults, or alcohol-impaired individuals. Annually, more than 5,000 pedestrians are killed and another 77,000 are injured in motor vehicle incidents. Pedestrian injuries that occur in rural areas are more likely to be fatal than those occurring in urban areas.
Because the problem is so complex—involving pedestrian and driver behaviors, road characteristics, travel patterns, vehicle speed, and environmental variables—no single intervention is likely to sufficiently reduce the number of pedestrian injuries. For example, infants are usually injured in strollers, toddlers are often injured in driveway backovers, and preschoolers and young elementary school-age children are often injured when they dart out between cars parked on residential streets, particularly during play. Adult pedestrian injuries often involve alcohol.
Multidisciplinary approaches involving theory-based education and training programs, engineering solutions, and strong law enforcement may be necessary to effectively reduce pedestrian injuries. Research should include interventions that focus not only on pedestrians, but also on drivers and the driving environment, such as strengthening enforcement strategies for speed limits, yield-to-pedestrian laws, and school zones. Changes in pedestrian and driver behaviors and modifications in roadway environments, including traffic-calming measures, may provide the strongest mix of prevention strategies. Research should develop and evaluate strategies that reduce the risk of collisions, such as increased pedestrian and vehicle visibility. Research should also address the different risk factors of various groups in urban and rural settings.
D.* Identify the underlying behavioral and situational factors associated with crashes involving teens; develop and evaluate appropriate interventions to address those factors.
In 1999, 5,700 teenagers died of injuries caused by motor vehicle crashes. Research shows that teenagers are more likely than other drivers to speed, run red lights, make illegal turns, ride with an intoxicated driver, and drive after using alcohol or drugs. They are more likely than other drivers to underestimate the dangers in hazardous situations, and they have less experience coping with those situations. Young people who drive after consuming alcohol pose an inordinate risk to themselves, their passengers, and other road users.
To prevent motor vehicle crashes among teens, research should evaluate strategies that limit their access to alcohol and that promote safety belt use. Research should also identify the behavioral and developmental characteristics that predispose some teens to take higher risks than their peers. Research to identify constellations of behavioral and developmental risk factors that could be used to develop and target interventions should focus on behavioral rather than epidemiologic studies. It should examine both protective factors and risk factors, such as the roles of supervision, family, peers, risk perception, decision-making skills, and community characteristics.
E.* Develop and evaluate interventions that address the proper and consistent use of measures to protect child occupants in motor vehicles.
In 1999 (the latest year for which fatality data are available), more than 1,100 children ages 15 and younger were killed while riding in motor vehicles. In 2000, nearly 330,000 were injured. Proper installation of age-appropriate child restraint systems, such as child safety seats or booster seats, and correct placement of children in restraints increase safety. Data show that Hispanic Americans have lower rates of child safety seat use than non-Hispanic Caucasian Americans. Research also shows that children seated in the back seat are safer than children seated in the front seat. Nevertheless, 47% of children killed in crashes are not seated in the back.
Further research about the efficacy and effectiveness of booster seats is needed to make reliable recommendations for children who have outgrown their child safety seats. Children usually do not fit into adult seat belts until they are 4’ 9" tall. Epidemiologic and biomechanic research are needed to document the efficacy of booster seats and to establish guidelines for their proper use based on variables such as age, height, weight, and other relevant anatomic dimensions.
Research might also assess the impact of child safety seat and booster seat laws as well as enforcement strategies and training/checking programs intended to increase proper use. Continued research is needed about the effectiveness of universal fasteners and alternative restraint designs, including devices that improve comfort and convenience. Research should evaluate strategies to improve proper use and decrease misuse of safety devices and to improve communication efforts to promote child occupant safety.
In addition to restraint use, research should investigate factors that influence drivers to place children in the back seat. The results of such research should guide intervention development, evaluation, and dissemination. A focus on special populations such as inner-city or non-English-speaking groups not reached by common communication channels is crucial.
F.* Among older adults, identify and measure factors that affect safe motor vehicle use.
Each year more than 7,000 persons ages 65 and older die in motor vehicle crashes, and 250,000 are injured. These numbers are likely to rise with the expected growth in this population segment. Many older adults change their transportation habits to allow for declining performance with age. For example, many stop driving at night because of vision problems. Yet little is known about how functional capacity, medical conditions, medications, and other factors affect safe motor vehicle use. Several approaches are available to document these relationships, including cognitive testing, simulator studies, and applied biomechanics research. Studying the effects of vehicle design on these human interactions is another potential direction for related research. Findings from these lines of research can be used to identify older adults at greatest risk and to design public health programs to reduce the risks of crashes and injuries among that group.
G. Develop and evaluate interventions to increase the use of occupant protection devices, such as seat belts, in high-risk and hard-to-reach populations.
Certain groups of people—such as inner-city, non-English-speaking, immigrant, and rural populations and those who do not perceive the risk of driving unprotected—are at higher risk for motor vehicle–related injuries and may also be difficult to reach with traditional prevention messages or interventions. Further reductions in motor vehicle–related injury rates will require tailoring interventions, such as those to increase seat belt use, to these groups.
Research should evaluate the effectiveness of changes in vehicle and restraint design and strategies to increase adoption and maintenance of seat belt use. Developing and conducting intervention research with hard-to-reach populations presents special challenges for any public health issue, including motor vehicle safety. Knowledge gained in this field, such as innovative recruitment techniques to engage study participants and elicit valid survey responses, may be useful to other areas of public health research. Investigations should include risk factor research to support prevention programs and interventions that are targeted, tailored, and evaluated.
H. Develop and evaluate interventions to reduce motorcycle crashes and injuries.
Motorcycle safety initiatives have placed their major emphasis on wearing helmets and on helmet laws to prevent crash-related head injuries and deaths. Research should continue to evaluate the effectiveness and sustainability of these interventions. It should also identify methods for promoting the most effective interventions and for identifying the barriers to implementing and sustaining effective interventions. Research should extend beyond the focus on helmets to determine the effectiveness of other strategies to prevent not only injuries and deaths but also crashes—strategies that involve motorcycle safety training, reduction of alcohol-impaired motorcycle driving, and licensing interventions. In addition to behavioral approaches, epidemiologic and biomechanic assessments of the effectiveness of different motorcycle helmet designs may improve rider safety. (See Sports, Recreation, and Exercise section for bicycle safety research.)
I. Develop and evaluate interventions to modify hazardous behaviors such as aggressive, inattentive, and drowsy driving.
Many motor vehicle crashes reportedly result from hazardous behaviors, such as aggressive, inattentive, and drowsy driving. Research should address both individual behavior-change strategies as well as community-based strategies that could reduce the impact of these types of risky behaviors on motor vehicle safety. Attention must be given to developing methods for measuring risky behavior, assessing its impact on crash risks and outcomes, and understanding the role of risk perception.
J. Develop and evaluate interventions to prevent crashes and injuries caused by modes of transportation other than motor vehicles.
While motor vehicle crashes are the most common cause of transportation-related fatalities and injuries, other modes of transportation also pose threats to public safety. Research is needed to identify strategies that prevent collisions, crashes, injuries, and deaths from other modes of transportation, such as railroad trains (including pedestrian-train and motor vehicle–train events), aviation, public transportation, and others.
K. Evaluate the effects of emerging vehicle technologies on the risks of crashes, the risk of injuries during crashes, and crash avoidance.
Various emerging technologies may improve traffic safety. However, these same technologies may have unintended negative consequences. For example, air bags provide additional crash protection in some situations but are known to place some smaller and younger occupants at greater risk. Also, windshield information displays may allow drivers to obtain more information while driving, but these same displays may exceed information processing thresholds or may confuse older drivers who have declining cognitive processing skills. Cellular telephones make calling for emergency assistance quick and easy, but they may also distract drivers. Research should evaluate how innovations such as side air bags, new seat designs, cellular phones, laser detection devices, and telematic and other devices affect driving performance, crashes, and injuries. Cognitive, biomechanic, and other hazards of new technologies should be investigated. Researchers should give attention to the impact of vehicle and auxiliary equipment design on changes in risk and in drivers’ perception of risk.
L. Identify the modifiable risk factors for and mechanisms of nonfatal neck, back, and soft tissue ("whiplash-like") injuries.
Research should focus on the epidemiology, biomechanics, and medical outcomes of nonfatal neck, back, and soft tissue ("whiplash-like") injury and should emphasize the research’s utility in prevention. Better knowledge of the types, severity, and mechanisms of such injuries is needed to assess accurately the public health impact and associated costs of the problem and to guide prevention strategies.
This page last reviewed September 07, 2006.