Throughout my medical career, I’ve heard statements like these:

Early detection offers the best chance of cure.

If you wait for symptoms, you’ve waited too long.

Knowledge is power, and the sooner you have the information, the better.

Over time, I’ve realized they are often untrue. Many health conditions go away on their own. In such cases, early testing may amount to wasted effort, time, and medical cost. Some testing is invasive and has a significant risk of complications. And minor abnormalities may lead to more testing. There’s also the anxiety of waiting for results, or learning you have an abnormality of uncertain importance that requires additional evaluation.

Why wait? Why not just test and treat right away?

Sometimes, the “cure” is the passage of time. That’s one reason many doctors will suggest watchful waiting rather than aggressive testing. Knowledge is only power if there’s something useful you can do with it. And many conditions aren’t worth knowing about or treating until they cause symptoms.

For these reasons, the American Board of Internal Medicine Foundation launched the Choosing Wisely campaign in 2012. Its mission is to encourage more selective, evidence-based testing and treatment, and to discourage unnecessary tests and care.

Six conditions for which early detection and treatment isn’t clearly helpful

• Certain leukemias and lymphomas. While malignant, some leukemias and lymphomas may progress so slowly that the risks of treatment outweigh the benefits. For example, no therapy may be recommended for early-stage chronic lymphocytic leukemia that is causing no symptoms.
• Sarcoidosis. This condition of unknown cause often causes enlarged lymph nodes and inflammation in a variety of organs. But when there are no symptoms, a normal physical examination, and normal results of routine testing, no treatment may be warranted.
• Some types of prostate cancer. For men with prostate cancer that has not spread outside the prostate gland and that has a nonaggressive appearance under the microscope, close monitoring without treatment may be advised. This recognition has led to uncertainty about whether to screen for prostate cancer (for example, with a blood test called PSA).
• Osteoarthritis. This is the most common type of arthritis and is nearly universal with advancing age. No treatment may be warranted if symptoms are mild.
• Mildly elevated LDL cholesterol in people at low risk for cardiovascular disease. Healthy lifestyle recommendations, such as getting regular exercise, losing excess weight, and choosing a healthy diet, are routinely recommended for this group, but medication is not.
• The common cold and many other viral infections. Our immune systems are able to fight off most viral infections without medications or other treatments. Treatment is usually limited to supportive measures (such as cold remedies, fluids, and fever reducers) and doesn’t depend on test results.

When not to wait: Tests to rule out a serious diagnosis

When there’s a significant suspicion for a serious condition in which early detection and treatment would make a difference, your health care provider should make every effort to figure that out sooner than later.

For example, if a chest x-ray reveals an abnormality suggesting cancer, further evaluation should be arranged promptly. If no cancer is found, that’s great — but it doesn’t mean the testing was unnecessary. Quickly ruling out a worrisome diagnosis that seems somewhat likely is often the reason that tests are recommended.

What about testing for peace of mind?

A person who feels unwell and doesn’t know why may be worried, distressed, or even depressed. It’s easy to imagine the worst, even if you know it’s unlikely. Getting a diagnosis — or ruling out a diagnosis — can provide reassurance and relief that can be profoundly helpful.

But often, reassurance can be provided without extensive testing. For example, imaging tests like an MRI aren’t recommended when a person has recently developed back pain, yet has no other symptoms or abnormalities during a physical examination, because we know the chance of finding something serious is quite small. Extensive, costly imaging is unnecessary — and might increase anxiety needlessly if an incidental abnormality of no consequence is discovered.

The reassurance value of early detection has been exploited by those who profit from it. Some imaging centers promote scans, ultrasounds, and other tests without the input of your doctor. Terrifying ads detail horrible things that might be going on right now in your body: Aneurysms about to burst! Nearly blocked arteries about to cause a stroke! Enlarging tumors on the verge of spreading throughout the body! Of course, these tests may not be covered by your health insurance, so these ads urge you to spend thousands of dollars for “peace of mind,” ignoring the evidence that such testing is generally not helpful and may cause harm.

Some organizations offer their executive leaders medical testing in excess of usual medical care. It’s considered an executive perk to have body scans looking for early disease to treat. Again, such testing has real downsides and, in my view, might not be much of a perk at all.

Early detection and treatment can be lifesaving — just not for every health issue

Certainly, there are many conditions for which the earlier the diagnosis, the better. That’s because we have effective treatments that work best during early stages of the illness. Breast and colon cancer, for example, can be cured if caught early enough. That’s why screening tests, including mammography and colonoscopy, are so important: they have the potential to detect an early tumor before it has progressed to an untreatable, ultimately fatal stage.

There are also noncancerous conditions in which early diagnosis and treatment improves outcomes: rheumatoid arthritis, appendicitis, and bacterial pneumonia are good examples.

The bottom line

The importance of early diagnosis and early treatment is clear for certain conditions. But for others, it’s oversold. The case could be made that our ability to test has outpaced our ability to interpret the results. Just because we can test for hundreds of diseases doesn’t mean we should.

The culture of American medicine has long been “more care — and more testing — is better care.” But as we spend more and more on healthcare without commensurate improvements in health, it’s worth reconsidering this assumption. If you feel unwell or have health concerns, talk to your doctor about how to proceed. But don’t be surprised if he or she recommends no specific treatment or testing. A plan to allow time to pass with close follow-up could save you the expense, anxiety, and risks of unnecessary care.

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