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Cutting alcohol consumption among college students nationwide is not only desirable, but also possible. A unique new University of North Carolina at Chapel Hill study concludes that correcting students' widespread misperceptions about how much other students drink helps to reduce drinking, especially heavy consumption.

What works are continuing public education campaigns that let students know that reports of campus drinking are routinely exaggerated across the country, that alcohol can seriously impair health and that one doesn't have to drink to excess -- or drink at all -- to fit in and have fun. Researchers say the programs simply publicize scientifically accurate information about local student drinking rates.

"Almost everybody misperceives how much college students actually drink," said Dr. Robert D. Foss, manager of alcohol studies at the UNC Highway Safety Research Center (HSRC). "When people are asked to estimate it, they almost always way overshoot the reality."

In 1997, with strong support from university officials, Foss and center colleagues began a first-of-its-kind study of drinking among UNC students by taking voluntary, anonymous breath-alcohol measurements as students returned to their residences on both weekend and weekday evenings. They found that two out of three -- even on weekends -- had nothing to drink, and many of the rest had only a few drinks. On Mondays through Wednesdays, typically, 85 percent did not drink.

"That survey gave us a clear view of student drinking that nobody else had before," Foss said. "Our findings ran counter to reports in the national media that portrayed excessive college student drinking as a rampant epidemic. Then, using an approach known as 'social norms marketing,' we publicized what many people found to be astonishing information -- that on traditional 'party' nights, Thursday through Saturday, two-thirds of students haven't had anything to drink."

They dubbed their program "2 out of 3." It included talks at first-year student orientation sessions, printed materials and posters distributed to every residence hall room and a financial incentive for students to display the posters. That turned out to be a highly effective way to remind students that drinking among their peers was moderate, he said.

In 1999 and again last October after every UNC undergraduate was potentially exposed to the alcohol education efforts, the team repeated the evening breath analysis surveys to learn whether changes in drinking had occurred. In all, they interviewed 6,352 undergraduates and measured the blood alcohol content of 6,108.

"The bottom line was that on a number of different measures, student drinking had declined," Foss said. "Self-reported drinking was down, self-reported heavy drinking, which some people call 'bingeing,' was down, and, most importantly, measured breath-alcohol concentrations were down. By 2002, the proportion of students with any alcohol had declined by 15 percent, and the proportion with a breath-alcohol concentration greater than 0.05 percent was down 23 percent."

Also by 2002, he said, 91 percent of all respondents were aware of the "2 out of 3" message, and 82 percent understood it. Also, 51 percent of first-year students and 45 percent of all respondents who understood it believed it accurately represented drinking at UNC.

"Although many students found the message difficult to believe, the percent of non-believers decreased noticeably from 1999 to 2002 -- from 65 percent to almost 50 percent," Foss said.

"The high degree of awareness and understanding of the '2 out of 3' message among UNC students indicates that the social norms program was successful in reaching its target audience," he said. "The increased belief in the accuracy of the campaign suggests that the primary message, which specifies that on 'party' nights most students drink little, if at all, is becoming more accepted as the reality of student drinking on campus."