The downside of medical screening

If you had a disease, and you could find out sooner rather than later, why wouldn't you? Medicine has long focused on early detection of diseases as part of a move toward preventive care. But imperfect tests, false positives, and overdiagnosis mean that sometimes the tests do more harm than good, and in recent years, there have been more recommendations to reduce some kinds of screening, including pap smears, colonoscopies, mammograms, and even annual pelvic exams. The more you look for disease, the more you find it. And in the case of cancer, it's hard for doctors to know if what they find is dangerous and needs to be addressed, or if it's just a small tumor that won't grow and poses no threat.