Though Budweiser has 9.1 percent of the national beer market, it represented 15 percent of the of the ER "market."
The disparity was even more pronounced for Steel Reserve. It has only .8 percent of the market nationally, but accounted for 14.7 percent of the ER market. In all, Steel Reserve, Colt 45, Bud Ice, and another malt liquor, King Cobra, account for only 2.4 percent of the U.S. beer market but accounted for 46 percent of the beer consumed by ER patients.
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"Some products are marketed to certain groups of people in our society," said Traci Toomey, the director of the University of Minnesota's alcohol epidemiology program, who was not involved in the study. Higher-alcohol malt liquor, for example, is heavily advertised in African-American neighborhoods.
"So we might want to put some controls on certain products if we find they are tied to greater risk," she said. "But how they are marketed and priced is critical information, and that has been very hard to study."
David Jernigan, a professor of public health at Johns Hopkins and the director of the study, told NBC News, "The Federal Trade Commission, in reports and in personal communication with me, said this kind of research cannot be done. The National Institute on Drug Abuse gave me similar push-back."
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Though Jernigan pointed out that no conclusions could be made about beer or malt liquor advertising, pricing, or even consumption based on the study because it was too small—105 patient interviews—and took place in only one hospital in Baltimore in mostly black neighborhood, he proved such research was possible.
By using a drop-down menu on a small notebook computer, the survey takers managed to obtain information from patients, and to include about 400 brands, in less than five minutes. At first, Jernigan, said, many patients refused to talk. But then the survey takers, with the permission of the emergency room staff, donned white coats. After that, patients talked freely.
Overall, malt liquor and lower-alcohol beer dominated consumption, but vodka, gin, brandy and cognac were overrepresented, too.
—By Brian Alexander for NBC News