Study about drunk fans has a limited sample

A recently released study suggests that 8 percent of fans leave sporting events drunk. This may be an interesting finding – but the newspaper description of the sample suggests there may be issues:

University of Minnesota researchers tested the blood alcohol content of 362 people to see how much folks drink when they go to professional baseball and football games. In their study, released Tuesday, they determined that 40 percent of the participants had some alcohol in their system and 8 percent were drunk, meaning their blood alcohol content was .08 or higher.

“Given the number of attendees at these sporting events, we can be talking about thousands of people leaving a professional sporting event who are legally intoxicated,” lead author Darin Erickson said. The study did not address what percentage, if any, of those fans intended to drive.

To collect the data, research staff waited outside 13 Major League Baseball and three National Football League games and randomly approached fans as they left. Those who consented took a breath test and answered questions about when, where and how much they drank on game day.

So the researchers waited outside 16 sporting events. Across these 16 events, the researchers performed voluntary tests on 362 people. This averages out to 22.625 fans per event.

Let’s say the events average at least 30,000 fans – not an unreasonable expectation for MLB and NFL games. If they tested about 23 fans at each event, that is less than 1 percent of each fans at each game. How could these findings be considered generalizable? First, you would need to test more fans. Second, could there be something different about the fans who were willing to volunteer for this test after a game?

Another report on this study bumps the sample number up a bit to 382 people. This doesn’t change the averages too much. Also, this may be the first study to examine the particular phenomenon of drinking at sporting events. However, the sample still seems to be too small even as the research study is going to be published in Alcoholism: Clinical & Experimental Research.

American drinking rate pretty steady

Gallup reports on the drinking rate in the United States which is up to a 15-year high of 71 percent. The drinking rate appears to be defined by asking whether someone uses alcoholic beverages or is a total abstainer.

While this 15-year high may seem remarkable, looking at the data from today back to 1939, the drinking rate has been “remarkably stable” (in Gallup’s words). Even in complex societies, some behaviors are quite steady over time.

As to what characteristics influence drinking, Gallup notes a few:

One of the most significant predictors of alcohol consumption is church attendance. Those who seldom or never attend church are substantially more likely than more frequent church attenders to say they drink; and those who have no religious identity, Catholics, and non-Christians are more likely to drink than Protestants…

59% of older Americans drink alcohol, substantially lower than the percentages among those who are younger. Additionally, those with the lowest education levels and lowest incomes are less likely to drink than others.

Interesting look at some common behavior. I wish there was a follow-up question (which I am sure is asked in other surveys): why do you or don’t you drink?