What factors determine whether a medical emergency is truly an emergency? According to a new study, the answer depends on how well your favorite baseball team is doing. A report published in the October issue of the Annals of Emergency Medicine reveals that the number of visits to emergency rooms in Boston-area hospitals was inversely related to how well the Red Sox performed in the 2004 World Series.

Previous studies had suggested a relationship between important sporting events such as the Super Bowl and hospital visits. John S. Brownstein of Children's Hospital in Boston and his colleagues tracked the number of patients in six area emergency rooms during 2004 playoff games involving the Red Sox. During games three and four of the American League Championship Series (ALCS), when the Red Sox were on the verge of being eliminated by the New York Yankees, the number of ER visits were slightly higher than average. But when the Sox started their comeback, hospital visits started to drop off. The researchers determined that there was an inverse relationship between the number of people watching a baseball game, based on Neilsen television ratings, and how busy the ER was. During the most popular games (game seven of the ALCS and game four of the World Series) hospital visits were 15 percent lower than expected based on historical data.

The scientists say that this is the first study to illustrate a direct dose-response relationship between the popularity of a sporting event and decreased use of hospital ERs. Notes co-author Kenneth D. Mandl of Harvard Medical School, "The public health finding here is people use discretion in deciding when to show up in the emergency department."