Road
Legal Drinking Age
Steering Columns
Child Safety Seats
Third Brake Light
Seat Belt Usage
Government Purchase of Airbags
Getting the Lead Out
Taiwan's Helmet Law
Injuries are the leading cause of death for youths aged 18-20 years, and alcohol is a risk factor for their mortality. Historically, the minimum legal drinking age (MLDA) in the United States has ranged from 18 to 21 years. In the 1970s and 1980s numerous state legislatures enacted changes in the MLDA. In 1970, 33 states had a MLDA of 21 years; between 1970 and 1975, 25 state legislatures lowered their MLDA to 18. Starting in 1977 many states began raising the MLDA, until by 1988 the minimum legal drinking was 21 in all states.
This "natural experiment" is the most well-studied alcohol control policy in United States history. At least 46 high quality studies find an inverse relationship between the drinking age and traffic crashes among 18-20 year olds; when the drinking age goes down, traffic injuries and fatalities among youth go up, and vice versa. The relationship holds even though there has been little or no active enforcement of the law in most states, and youth still have some access to alcohol. The National Highway Traffic Safety Administration estimates that traffic fatalities have fallen by almost 1,000 deaths per year due to the higher MLDA. The 21-year legal drinking age probably also reduced other injuries; one study found an 8% reduction in youth suicides for a 21- rather than 18-year old drinking age.
Moral: Laws can have a beneficial effect, even when there is little enforcement, and some people flout the law.
Sources:
Wagenaar AC, Toomey TL. Effects of minimum drinking age laws: review and analyses of the literature from 1960 to 2000. Journal of Studies on Alcohol, supplement No. 14: 2002, 206-225.
Voas RB, Tippetts AS, Fell JC. Assessing the effectiveness of legal drinking age and zero tolerance laws in the United States. Accident Analysis and Prevention. 2003; 35:579-587.
Birckmayer J, Hemenway D. Minimum-age drinking laws and youth suicide, 1970-1990. American Journal of Public Health. 1999; 89:1365-1368.
Energy-absorbing Steering Columns
The steering assembly is the most common source of serious injury for drivers in frontal crashes. In passenger cars, before the 1967 model year, the steering column in most cars was a rigid pole ending in a narrow hub. It was like a spear pointed at the chest of the driver. In frontal crashes, the driver would hit the rigid column with the force concentrated on the narrow hub. Even worse, the steering column would often be propelled rearwards, toward the driver at a high rate of speed. Not surprisingly, the driver's lungs and other internal organs would be punctured, and the driver would often die.
In the 1960s, the General Services Administration began requiring improved steering assemblies in government purchased vehicles. In 1967, the new National Highway Traffic Safety Administration extended this requirement to all new passenger cars sold in the United States. A comprehensive analysis of the safety benefits estimated that these safer steering assemblies reduced the risk of driver fatality in frontal crash by 12% and the risk serious injury to the driver by over 17%. For 1978 alone, that meant 1,300 fewer driver deaths and 24,200 fewer serious injuries. The average lifetime cost to the consumer for this safety improvement was only ten dollars and fifty cents per car. Most motorists were unaware of this important safety improvement.
Moral: Many important public health policies benefit individuals without their awareness.
Sources:
Kahane, Charles J. An evaluation of federal motor vehicle safety standards for passenger car steering assemblies. NHTSA Report Number DOT HS 805-705, January 1981.
Evans, Leonard. Traffic Safety. Bloomfield Hills, MI: Science Serving Society. 2004.
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Child Safety Seats
In the 1970s, the major policy initiatives in child passenger safety were educational. When it became clear that education alone was not sufficiently changing parental behavior, a small group of pediatricians in Tennessee lobbied that parents be required by law to restrain small children in their cars. A legislator might be approached by the very pediatrician who had cared for his children. In 1978, Tennessee became the first state to mandate child safety seat use. Between 1978-1983 in Tennessee, occupant deaths to children under age 4 declined by more than 50%. Children not in a restraint device were 11 times more likely to die in a crash than those who were restrained.
By 1985, every state had passed child seat restraint legislation. Safety seat use in cities rose from 23% in 1982 to 82% in 1987.
Moral: A few determined people can save many innocent lives.
Sources:
Decker MD, Dewey MJ, Hutcheson RH Jr., Schaffner W. The use and efficacy of child restraint devices: the Tennessee experience, 1982 and 1983. JAMA. 1984; 252:2571-2575.
Kalbfleisch J, Rivara F. Principles in injury control: lessons to be learned from child safety seats. Pediatric Emergency Care. 1989; 5:131-134
Editorial. Celebrating the first child passenger safety law. Safe Ride News. Spring, 1998. p. 2.
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Third brake light
Rear-impact collisions account for more than 20% of all motor vehicle crashes. In 1993, for example, it is estimated that there were more than 1.5 million rear impact crashes, and over 600,000 injured occupants. Countermeasures intended to reduce the problem have included head restraints, crash resistant gasoline tanks, stronger bumpers, and improved brake lights. Between 1977-1980, fleets of taxicabs and telephone company passenger cars were randomly provided with center high mounted stop lamps. The cars so fitted experienced 44%-54% fewer rear end collisions while braking than those cars without this third brake light.
Based on such studies, the National Highway Traffic Safety Administration required that all passenger cars manufactured after August 1985 be equipped with a center high mounted stop lamp. Studies find that these lights have reduced rear end collisions, but by only 4%-5%. Part of the reason for the lower levels of effectiveness is that drivers may have become acclimatized to the new lights, as the "novelty effect" wore off. Still, even a 4% reduction in rear end collisions may represent some 25,000 injuries prevented each year.
Moral: Safety devices work, but often have less of a real world impact than might be predicted.
Sources:
Farmer CM. Effectiveness estimates for center high mounted stop lamps: a six-year study. Accident Analysis and Prevention. 1996; 28:201-208.
Kahane CJ. The long-term effectiveness of center high mounted stop lamps in passenger cars and light trucks. NHTSA Technical Report Number DOT HS 808-696. March 1998. Available at http://www.nhtra.dot.gov/cars/rules/regrev/evaluate/808696html
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The efficacy of seat belts in reducing mortality and morbidity in traffic crashes has been well established. A problem has been getting motorists to buckle up. In 1980, for example, only 11% of the motoring population wore seat belts. By 1999 that percentage had increased to 71%, a clear injury prevention success story. The National Highway Traffic Safety Administration estimates that seat belts probably saved more than 11,000 lives in 1999 alone.
The big jump in U.S. seat belt use came between 1984 and 1992, when usage rates went from 14% to 62%. In 1984 the U.S. Secretary of Transportation ruled that passive restraints (e.g. air bags) would not be required in motor vehicles if more than 2/3 of the nation's population resided in states with mandatory seat belt laws (meeting five specific criteria). The auto industry, which had long fought passive restraint requirements for their vehicles, immediately began a massive lobbying campaign to enact state seat belt laws, forming a new organization, Traffic Safety Now, to spearhead the effort. While no state had a seat belt law in 1983, by the time Traffic Safety Now closed its doors in 1992, 42 states had enacted seat belt laws. In a ironic twist for the auto companies, but of great benefit for safety, it was ruled that many of the state laws did not satisfy the criteria in the regulation, and the U.S. ended up with both state seat belt laws AND automobile air bags.
Moral: Industry often has the power, but not sufficient incentive, to successfully push for laws promoting consumer safety.
Sources:
Haseltine PW. Seat belt use in motor vehicles: the U.S. experience. 2001 Seat Belt Summit: Policy Options for Increasing Seat Belt Use in the United States in 2001 and Beyond. . January, 2001. http://www.actsinc.org/Acrobat/SeatbeltSummit2000.pdf
Graham, JD. Auto Safety: Assessing America's Performance, Auburn House Publishing Company, Dover, MA, 1989.
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Government Purchase of Airbags
Government-mandated motor vehicle airbags are currently saving the lives of thousands of motorists each year. The struggle to ensure that motor vehicles were equipped with such passive restraint systems was a long and tortuous one. One step along the way was the purchase by the General Services Administration (GSA) in 1985 of 5,000 airbag-equipped vehicles.
Ralph Nader and progressive insurance companies helped convince the GSA chief to try to purchase vehicles equipped with airbags for the federal government's automotive fleet. With some government subsidies, Ford finally agreed to provide airbag-equipped Tempos. The exemplary safety performance of these air bags provided real world evidence for government mandating this safety device.
Gerald Carmen, Republican businessman and the head of GSA at the time, calls the airbag purchase "an exciting adventure, initiated by Nader, supported by the insurance companies, and a real success story for GSA."
Moral: Government procurement can be used to promote safety and reduce injury.
Sources:
Hemenway D. Government procurement leverage. Journal of Public Health Policy. 1989; 10:123-125.
Graham JD. Auto Safety: Assessing America's Performance. Dover, MA: Auburn. 1989.
Lead is a major environmental health hazard to adults, but especially to young children. High blood lead levels can result in lowered intelligence (e.g. IQ), learning disabilities, impaired hearing, reduced attention span, hyperactivity, and antisocial behavior. Until the late 1970s, ambient concentrations of lead (from lead that was added to gasoline) were a major contributor to childhood lead poisoning.
In 1972 the Environmental Protection Agency launched an initiative to phase out leaded gasoline. By 1986 the primary phaseout of leaded gas in the U.S. was complete. Average blood levels in children under age 6 fell 78% between the late 1970s and the early 1990s. The decline was largely due to the phasing out of lead in gasoline (some of the decline was due to legislation banning lead from paint and plumbing supplies). Unfortunately, many non-high-income nations still (2004) allow lead to be added to gasoline.
Moral: Public health may not be the first concern of industry
Sources:
U.S. Environmental Protection Agency. America's Children and the Environment: A First View of Available Measures. December 2000.
http://yosemite.epa.gov/ochp/ochpweb.nsf/content/ACE-Report.htm/$file/ACE-Report.pdf
Kitman JL. The Secret History of Lead: A Special Report. The Nation. March 20, 2000.
http://www.thenation.com/doc.mhtml?i=20000320&c=1&s=kitman
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Taiwan's Helmet Law
Taiwan has one of the highest motorcycle use rates in the world; over two thirds of their motor vehicles are motorcycles. In mid-1997, Taiwan followed most other Asian countries by enacting a mandatory helmet use law for cyclists. Mandatory helmet laws are easily enforced because non-compliance is readily observed. Helmet use rose immediately, from about 20% to over 95%. The number of licensed cyclists remained the same. In the first six months fatalities due to motorcycle head injuries fell 22% (all motor-cycle related deaths fell 14%) and non-fatal head injuries fell 44%. Although almost all cyclists wore helmets, over half of all motorcyle-related head injuries were to individuals who were not wearing a helmet.
Moral: Sometimes it takes legislation to change behavior and improve public health and safety.
Sources:
Tsai MC, Hemenway D. Effect of the mandatory helmet law in Taiwan. Injury Prevention. 1999; 5:290-91.
Chiu WT, Kuo CY, Hung CC et al. The effect of the Taiwan motorcycle helmet use law on head injuries. American Journal of Public Health. 2000; 90:793-96.
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