Screening tests you probably don’t need

You’ve probably had more than a few screening tests—blood pressure and cholesterol checks, mammograms, Pap smears, and colonoscopies. However, health fairs and clinics often promote screening tests you might not have had. If you’ve wondered whether they’re a worthwhile investment in your health, the United States Preventive Services Task Force (USPSTF) can help you. The USPSTF is a panel of primary care physicians and epidemiologists appointed and funded by the U.S. Department of Health and Human Services. Its role is to develop clinical practice guidelines—recommendations for clinicians about the care of patients with specific conditions. Other health organizations also develop guidelines.

“We’ve known for some time that there is a wide variation in the way medicine is practiced across parts of the country,” says Dr. Mark Aronson, professor of medicine at Harvard Medical School. “Guidelines are based upon the best available research evidence and practice experience and are meant to give guidance to doctors for best practices.”

To develop guidelines for screening tests, panelists weigh the evidence of the potential benefits and risks of administering the tests to millions of people who have no signs of disease. In doing so, they take into account the quality of evidence—for example, whether it is from “gold standard” randomized controlled trials, observational investigations, or case studies. (For more on these types of studies, see “Two types of studies.”) The USPSTF then issues guidelines suggesting who might benefit from the tests and who might not. As new evidence emerges, the panelists reassess the guidelines and issue new ones if necessary.

Tests the USPSTF doesn’t recommend

If you have no cardiovascular symptoms and are at low risk, you can probably skip the following tests:

Electrocardiogram. This test, also known as an ECG, reveals abnormalities in the heart’s electrical activity. The USPSTF recommends against using an ECG to predict the likelihood of heart attacks or related problems in people at low risk for heart disease and says that there isn’t enough evidence to determine whether it is useful for people at higher risk.

Carotid artery screening. Ultrasound imaging to detect narrowing of the carotid arteries, which pass through the neck to the brain, has been touted as a way to predict an increased risk of stroke. However, the USPSTF recommends against the test because there is little evidence to indicate that narrowed carotids increase stroke risk in asymptomatic people. Moreover, the test may lead to additional procedures, such as a carotid angioplasty (a surgical procedure to widen the artery), which has a modest but real risk of complications.

Abdominal aortic aneurysm screening. If the wall of the aorta weakens, it can develop an aneurysm, or bulge, that may rupture, often leading to fatal bleeding. These aneurysms are more common in older men than in women and in smokers than nonsmokers. The USPSTF recommends against this test for women who have never smoked and says there isn’t enough evidence to make a recommendation for older women who are current or former smokers.

Other questionable tests

The USPSTF hasn’t issued guidelines for the following tests, but no expert organizations endorse them for screening healthy women.

Whole-body CT scans. Many imaging centers promote full-body CT (computed tomography) to screen for tumors, aneurysms, osteoporosis, hernias, kidney stones, and gallstones. However, the procedure hasn’t been rigorously tested for that purpose. In fact, the National Cancer Institute warns that most abnormal findings on these tests do not indicate a serious health problem, but can lead to biopsies and other follow-up tests that are expensive, inconvenient, and uncomfortable. In addition, whole-body CT delivers about four times the estimated average annual dose of natural radiation.

Coronary artery calcium score. A CT scan of the coronary arteries can detect calcium deposits that may signify an in-creased risk of heart attacks. The results of the scan are used to compute a coronary artery calcium (CAC) score. The USPSTF is currently evaluating the use of the CAC for screening. In the meantime, if your doctor hasn’t advised you to have this test, there’s no good reason to get it on your own.

The bottom line

The current USPSTF guidelines are at https://www.uspreventiveservicestaskforce.org/. Keep in mind that they have been developed for the general population. Only you and your doctor can decide on the screening schedule that is best for you.