Sagittarians are 38% more likely to break a leg than people of other star signs -- and Leos are 15% more likely to suffer from internal bleeding. So says a 2006 Canadian study that looked at the reasons residents of Ontario province had unplanned stays in the hospital.
Leos, Sagittarians: There's no need to worry. Even the study's authors don't believe their results.
They're illustrating a point -- that a scientific approach used in many human studies often leads to findings that are flat-out wrong.
Such studies make headlines every day, and often, as the public knows too well, they contradict each other. One week we may hear that pets are good for your health, the next week that they aren't. One month, cellphone use causes brain cancer; the next month, it doesn't.
"It's the cure of the week or the killer of the week, the danger of the week," says Dr. Barry Kramer, associate director for disease prevention at the National Institutes of Health in Bethesda, Md. It's like treating people to an endless regimen of whiplash, he says.
Take the case of just one item: coffee. Drinking two or three cups per day can triple the risk of pancreatic cancer, according to a 1981 study. Not so, concluded a larger follow-up study published in 2001.
Coffee reduces the risk of colorectal cancer, found a 1998 study. Not so, according to one published later, in 2005.
"I've seen so many contradictory studies with coffee that I've come to ignore them all," says Donald Berry, chair of the department of biostatistics at the University of Texas MD Anderson Cancer Center in Houston.
"What about the man on the street?" asks Stan Young, a statistician at the National Institute of Statistical Sciences in Research Triangle Park, N.C. "He reads about coffee causing and not causing cancer -- so many contradictory findings he begins to think, 'I don't trust anything these scientists are saying.' "
These critics say the reason this keeps happening is simple: Far too many of these epidemiological studies -- in which the habits and other factors of large populations of people are tracked, sometimes for years -- are wrong and should be ignored.
In fact, some of these critics say, more than half of all epidemiological studies are incorrect.
The studies can be influential. Often, in response to them, members of the public will go out and dose themselves with this vitamin or that foodstuff.
