Cheaper beer prompts heavier drinking by college students. That's the chief finding of a new study by researchers at the Harvard School of Public Health, who found a strong correlation between the prevalence of alcohol promotions, such as sales on bulk purchases, and high rates of student drinking.

The study, which appears in the October issue of the American Journal of Preventive Medicine, was based on "independent observations" of 1,684 convenience stores and other businesses that sell alcohol but that do not allow its consumption on the premises, and 830 bars and clubs.

According to the study, in retail outlets surrounding college campuses, the average price of a 24-pack of beer was $11.74. Researchers found that the lower the price of a 24-pack, the higher the rate of student drinking on that campus.

The study suggests that regulating marketing practices would be an important strategy in reducing drinking among students.

"High-volume, low-priced sales are an important factor in fueling destructive drinking practices," said Henry Wechsler, who led the study and is director of college alcohol studies at the Harvard School of Public Health.

The text of the study can be found on the school's Web site.