Medical Tests: The Illusion of Reassurance

Recently researchers asked a question that seems less like science, and more like science-fiction: Is it more comforting to have a medical test or to see a doctor?

If tests can provide more empathy than doctors, the rise of the machines is nigh. And yet, as a physician, I am sad to say that the question is apt. Tests are increasingly common, visits are increasingly short, and doctors now commonly forego thorough physical examination. Put bluntly, in the exam room we are already doing less talking and touching, and more testing.

The new research, published earlier this year in JAMA-Internal Medicine , examined data from 14 studies of nearly 4,000 concerned but healthy patients. Each was randomly assigned to have, or not have, tests like endoscopy or stress tests added to their doctor visit. In the weeks and months that followed the investigators then compared the two groups on "illness concern" and anxiety. The results turn conventional wisdom on its head.

It is an open secret that doctors routinely order tests to reassure their patients, yet testing provided no more reassurance than a doctor visit alone. "Most patients seemed to get better or be reassured even without testing," according to Dr. Christopher Burton, a researcher from the University of Aberdeen. He sees a lesson in the results. "Testing for reassurance is not good medicine."

Burton is not alone in this opinion. Choosing Wisely , a physician-led campaign to raise awareness of over-testing, seeks to reduce tests unlikely to improve health, including those done for reassurance. President Obama's signature legislation, the Affordable Care Act, similarly rewards providers for testing and treatment habits that reap the most medical benefit while discouraging the rest.

And yet, the allure of testing is real. CAT scanning, for instance, offers the eyes of technology, and physicians are trained information gatherers. What could be wrong with more information?

"They're looking for certainty and it's a fallacy," says Dr. Kurt Kroenke, a leading researcher on the role of medical testing. Dr. Kroenke, a professor of medicine at the University of Indiana, points out that even highly accurate tests can be wrong. Moreover, "When you're testing for reassurance you get into trouble with false positives, which actually create uncertainty." In an editorial Dr. Kroenke notes that the low chance of serious illness -- less than 3 percent in the research -- means that most of the "abnormalities" found on testing were actually mistakes.

Kroenke's point is vital. Doctors and patients often forget that abnormal, or "positive," test results are typically right when illness was likely, but wrong when it was unlikely. This calculus helps to explain, for instance, why more than 90 percent of positive mammograms are typically false: Screening is done, by definition, on people without signs or symptoms of cancer. That's a group very unlikely to have disease -- just like patients for whom testing is primarily a matter of reassurance.

This quirk in the math may help to explain a disturbing finding in the research: Patients who underwent testing reported higher levels of anxiety weeks and months later. The finding was statistically borderline, but hints that testing for reassurance may have the opposite effect, probably because of false positives that lead to more tests and procedures.

Of course, for physicians, pressured by time, increasingly challenged by satisfaction surveys, and threatened by lawsuits, tests are hard to resist. Patients often want them and may even request them, and ordering a test takes little or no time from the doctor. As Dr. Kroenke points out, for the physician, "it often takes more effort and time not to order a test."

And this may be the most important discovery of all. Ordering a test, the quickest, easiest, but costliest option, not only failed to achieve the reassurance patients were seeking, it increased anxiety and led to potentially dangerous false positives. Meanwhile, talk and touch, which reduces lawsuits , promotes healing , and increases satisfaction , took time and effort but cost little more than a few extra minutes in the exam room.

Good medicine, it seems, is less like science fiction, and more like science.