Motor vehicle crashes are the leading cause of death for 15- to 20-year-old youth in the United States, according to mortality data from the National Center for Health Statistics. More than one quarter of the drivers killed in crashes had been drinking. While all school-based alcohol prevention programs strive to minimize alcohol use and/or misuse, little is known about the actual effects of these programs, particularly on students’ driving. A study in the March issue of Alcoholism: Clinical & Experimental Research examines the effects of a high school-based alcohol misuse prevention program on participants’ subsequent driving behaviors.
"A law setting a minimum drinking age of 21 years exists in all the states," explained Jean T. Shope, senior research scientist with the Transportation Research Institute at the University of Michigan and lead author of the study. "Although it has reduced underage drinking and driving fatalities, we still have a problem."
In 1999, according to the National Highway Traffic Safety Administration, 3,561 drivers 15 to 20 years old were killed - and an additional 362,000 injured - in traffic crashes. Of those young drivers fatally injured, 29 percent had been drinking. Although driving after drinking is potentially deadly under any circumstances, it is particularly dangerous when teenagers do it.
"It’s important to look at the context of this behavior," said James Hedlund, a consultant in traffic safety for Highway Safety North. "Not only is their drinking illegal, because the minimum drinking age in the United States is 21 years of age, but so too is their driving after drinking. Every state has a zero-tolerance law." Under these laws, teenage drivers detected with a blood alcohol concentration of 0.02 grams per deciliter or above will lose their driver’s licenses. "So drinking after driving is doubly illegal," he said.
"There are two overall methods to change someone’s behavior: enforcement, and education," added Hedlund. "Legal interventions have been evaluated best, because they go into place at one given time, all over a state. But a high school prevention program doesn’t work that way. It’s usually put into place in one high school, often for a short period of time, and it’s very difficult to measure its effects. One of the really good things about Shope’s study is that she finds effects in long-term traffic offense data."
Shope’s research is a follow-up to the Alcohol Misuse Prevention Study, in which five hour’s worth of alcohol-education sessions were given to 10th-grade Michigan students during each of the 1988-1989 and 1989-1990 school years. For this study, Shope and her colleagues examined students’ driving histories for roughly seven years following licensure, which typically occurs during or shortly after 10th grade. The study had three main findings.
"They found that the curriculum reduced serious traffic offenses, both alcohol-related offenses and other offenses as well, by about 20 percent in the first year these kids were licensed to drive," said Hedlund. "Second, the effect disappeared after the first year of driving. Third, the effect in the first year was strongest in two particular groups of students: those who didn’t drink very much, and those who had parents who didn’t seem to disapprove much of teen drinking."
Shope refers to the first finding as a "nearly significant decrease in serious offenses" among the group that received the alcohol-prevention sessions. This means that, statistically speaking, the finding was marginal. Nonetheless, said Shope, "it’s an intriguing finding, and it certainly looks like we did make a difference." She was more enthusiastic about the finding concerning the sub-group of teens who were drinking less than one drink per week at the time of the program.
"I think it’s important that the prevention program seemed to work best among the group that had not yet started to drink," Shope said. "This is a typical finding in prevention. To get to them at the right time makes all the difference. It’s just like trying to prevent smoking; you need to stop them before the age of 13. We already know that drinking increases very much during high school. If you’re going to do prevention, you have to get in there before the behavior starts, otherwise you’re doing treatment or harm reduction, not prevention."
"This is one of the few studies I know that looks at an educational program and actually finds some bottom-line results of observable behavior," said Hedlund. "It gives some scientific data that say you really can teach high school kids something. I’m saying that only somewhat facetiously. This is a very difficult group to try to educate, especially in ways that are socially responsible, when a lot of these kids are looking for ways to be socially irresponsible. So it’s good news that this study gives us some indication that education about socially acceptable behaviors may indeed make a bottom-line difference. The results aren’t conclusive, but they are very promising."
Apart from the findings themselves, Shope said the study also raises several other points. "There really needs to be more follow-up or long-term evaluation of prevention programs," she said. "We also need longer-term intervention or teaching. Why would a five-hour program in 10th grade, with no revisiting of the topic … why would that have much of an effect? Sometimes these school programs are just a drop in the bucket when there’s a lot of other stuff going on in a young person’s life. You can’t really expect a whole lot of change from a tiny little effort. One more thing, while schools may be very convenient places to reach groups of young people, many of these programs would work much better if the same message were also being delivered from the home, family, community, youth organizations, and the media. Prevention can be somewhat ‘swimming up stream’ when it’s not really being reinforced anywhere else."