Underage drinking has decreased since its peak in the late 1970s, but drinking by youths has stabilized at disturbingly high levels, researchers say.

Analysis of three ongoing national studies found that almost 80 percent of adolescents have consumed alcohol by the time they are 12th-graders. About 12 percent of 8th-graders have consumed five or more drinks on a single occasion within the past two weeks.

Researchers used a technique designed to look at long-term trends rather than year-to-year changes to look for significant indicators.

The analyses showed an increase in youth drinking in the late 1970s, followed by a long period of decreases until the early 1990s. The authors noted that the decline in underage drinking rates during this period probably reflected the increase in the minimum legal drinking age from 18 to 21. Since the early 1990s, all three surveys included in this analysis indicate relatively stable rates for underage drinking.

"Stable is better than up," said researcher Vivian Faden. "However, the current stability in youth drinking prevalence is quite worrisome."

Rates for any alcohol use in the past 30 days range from 19.6 percent of 8th-graders to 48.6 percent of 12th-graders. The data also show that more than 12 percent of 8th-graders and nearly 30 percent of 12th-graders report drinking five or more drinks in a row in the past two weeks.

"Much remains to be done to get those numbers moving down again," Faden said. "We need to re-examine the approaches we have taken to prevent underage drinking, so that in another 10 years we can report a downturn in this high-prevalence behavior instead of a stable situation."

The findings, part of a new analysis of youth drinking trends by researchers at the National Institutes of Health, appear in the September 2004 issue of Alcoholism: Clinical and Experimental Research.