During your next routine medical checkup you have at least a 43 percent chance of undergoing an unnecessary medical test, a new study shows. It's not like you're getting something for nothing. If you're not having symptoms, and your doctor has no reason to suspect you have a problem, U.S. guidelines advise against giving you a routine urinalysis, electrocardiogram, or X-ray. This has more harm than benefit," says Dan Merenstein, M.D., director of research in family medicine at Georgetown University. "The problem is, there are so many false-positive results from these tests. They lead to other things, like biopsies." The tests are meant to help doctors explore specific symptoms that are troubling patients or raise suspicion of a problem. If you're a healthy person who's just getting a routine checkup, there's only a tiny chance the tests will find disease. But Merenstein points out there's a good chance the tests will get a slightly abnormal finding. That means further costly tests - maybe even a painful biopsy - to show that you were, indeed, perfectly healthy to begin with. Aside from the costs in time and the potential for unnecessary suffering, these procedures add up to big money. Merenstein's modest estimate of the cost of just these three simple tests is $47 million to $194 million a year. And that doesn't include the cost of follow-up tests.