In addition to federal regulation, states and local governments have extensive regulatory and administrative responsibilities for highway safety, including driver licensing, driver education programs, motor vehicle inspections, setting speed limits, highway and road design and maintenance upgrades, and legislation and enforcement of traffic safety laws including those on alcohol-impaired driving, safety belt use, and use of child safety seats.
The national objective of reducing motor vehicle injuries has been pursued under the constraint that regulations were to be aimed at improving safety per vehicle mile, without attempting to influence the amount that people drive. Policies such as improved public transportation, higher gas taxes, mixed-use zoning (access to goods and services available within residential areas), and others have been advocated at various times and places, but usually not in the context of the nation's effort to improve highway safety.
There has been a significant federal, state, and private-sector investment in highway and traffic safety research. This multidisciplinary effort has focused on each of the four principal elements affecting motor vehicle safety—the human (driver and occupant), the vehicle, the roadway, and the socioeconomic environment. Increasingly sophisticated research has enriched the empirical foundation for informed policy debate and has led to improved safety features and effective prevention programs. Biomechanics research has provided information on injury mechanisms and human tolerances to trauma that has been used in testing vehicle crashworthiness and improving safety measures. Interventions to reduce alcohol-impaired driving and other human factors that affect highway safety have been developed and evaluated through extensive behavioral research. Engineering, highway planning, and other disciplines have contributed to improved vehicle and highway design and to the development of safety-enhancing features such as center high-mounted rear brake lights, improved tire and brake performance, breakaway sign and light poles, protective guardrails, and work-zone safety measures (TRB, 1990). Research by emergency medical services (EMS) and trauma care professionals has improved trauma services and trauma care, and rehabilitation specialists have focused research efforts on improving outcomes for individuals with traumatic brain injury or spinal cord injury due to motor vehicle crashes.
Several federal agencies fund motor vehicle safety research. NHTSA funds research primarily on human factors and vehicle safety, while the Federal Highway Administration funds research on improving highway safety. Additionally, other federal agencies have focused on topic-specific transportation safety research. For example, the National Institute on Aging funds some research on the effects of aging on driving performance; the National Institute on Alcohol Abuse and Alcoholism has funded some research on the effect of alcohol on motor