You can now perform a startling number of medical tests from the privacy of your home. But are they accurate?
By Dr. Mehmet Oz
I'm all for patients taking an active role in monitoring their own health, and to that end self-screening can be very useful. Finger-prick tests, for example, have revolutionized the way diabetics measure their blood-sugar levels throughout the day, and at-home pregnancy tests have been the standard for decades. But as tests providing more complex health information come on the market, the risk of misinterpreting results increases. Here's how to know which questions you can answer on your own and which are better left to the pros.
How is My Cholesterol?
At-home cholesterol tests that have been approved by the Food and Drug Administration are nearly as accurate as professional versions (and require just a few drops of blood), but you're still better off having your doctor analyze the results. Here's why: Many kits determine only your total cholesterol, yet what really matters is how that number breaks down between LDL (the bad kind) and HDL (the good kind). Even if you choose a test that can give you all those details, it still doesn't paint a full picture of your risk for heart disease. When I go over a patient's results, I consider the whole person—age, family history, other health issues—in order to make the right call.
Am I Allergic to Wheat? Ragweed? My Cat?
There's now a quick way to test for common allergens, from dust mites to milk, at home. You do have to mail a small sample of your blood to a lab for processing, but you can access your results online in just a few days. Still, while you can get some valid info, keep in mind that allergists typically use skin tests (in which the skin is exposed to an allergen to see whether there's a reaction) because they're considered more sensitive than blood testing. In fact, one Johns Hopkins study found that blood tests can fail to detect antibodies, as well as overestimate or underestimate the body's immune response to certain foods. Bottom line: Even if you choose to test at home, have a doctor review the findings.
Do I Have a UTI?
Urinary tract infections account for about 8.1 million doctor visits a year—and by age 32, half of all women report having had at least one. A home dipstick test, much like the one your doctor uses, detects nitrites (and, with some tests, white blood cells as well) in your urine. High levels are probably a sign of infection. This isn't the type of at-home test you want to use for a first-time diagnosis, though; serious kidney problems and STDs often have symptoms similar to those of a UTI, so you'll want your doctor to rule out those issues right away. But if you're familiar with your UTI symptoms (for women the risk of recurrence increases with each infection), your doctor may give you the green light to test at home and phone in the results.
Can I Have Kids?
In the wake of home ovulation tests, DIY fertility screening is increasing in popularity. These tests measure the level of follicle-stimulating hormone (FSH) in your urine on the third day of your menstrual cycle. Why FSH? It's the hormone produced by the pituitary gland that signals to your ovaries that it's time for an egg to grow and mature; if you're infertile (or in menopause), the signal isn't received, and, as a result, your pituitary sends another surge of FSH, elevating your levels in the process. But interpreting an FSH test is not clear-cut: A 2012 study found that women who reported high FSH levels didn't end up having a significantly lower chance of conceiving than women with normal levels. If you have concerns about your fertility, the best thing you can do is consult your doctor.
Mehmet Oz, MD, is the host of The Dr. Oz Show (weekdays; check local listings).