Mariska Leeflang, researcher at Amsterdam UMC, first explains the difference between a self-test and a home test. “You do self-tests at home and you also read the results yourself, such as with a corona test or a pregnancy test. With a home test, you take material at home, for example blood or urine, but send it to a laboratory. The analysis is done there.” In principle, the latter offers more warranty, although that does not say everything about the quality.
According to GP Jojanneke Kant, known to many as the Question Doctor on Instagram, more and more people are taking a test before entering her consultation room. “Hormone tests are especially popular: testosterone, cortisol or whether someone is going through menopause.” She welcomes involvement in her own health, but has reservations. “We often conclude together that it was a waste of money.”
A well-known example is the menopause test (a test for women to see whether they are going through menopause). “The only way to determine that you are truly in menopause is if you haven’t had a period for a year,” says Kant. “You don’t have to measure that in your blood. You notice that yourself.” Yet there are plenty of hormone tests being sold that suggest they provide clarity.
Reliability
Leeflang has been conducting research into the reliability of diagnostic tests for years. Her conclusion is cautious, but clear: “You can’t say much about the reliability of many self-tests.” Manufacturers often quote impressive percentages, such as 95 or 98 percent reliable. But it is not always possible to find out where those figures come from. “If you start looking for substantiation, it often turns out not to be found.”
The fact that one test is not the same as the other is also evident from research into self-administered chlamydia tests. “The reliability varied from 20 to over 90 percent,” says Leeflang. Without insight into how and on whom such a test was tested, a percentage means little.
There is also something else: administering the test correctly. Blood tests often require you to prick your finger and collect enough blood. This proves difficult in practice, says Kant. “Someone recently came to my office to fill the tube together, because it had not worked at home. Then we filled the tube together.”
