2 ms·
> For many real tests, getting a false positive once predicts a higher chance of getting another false positive in a repeated test. Almost all of them, in fact
by dmurray 5y ago
> For many real tests, getting a false positive once predicts a higher chance of getting another false positive in a repeated test.
Almost all of them, in fact. If improving accuracy was as easy as repeating the test, the doctors would just be told that the correct procedure for this test is to take three readings.
You can expect that this is untrue only if the tests are especially expensive or invasive.
- HWR_14 5y agoI believe repeating the test is standard procedure for many tests - if the first one is positive. However the repetitions are usually temporally separated (in some cases intentionally, in others because the test takes time.) This is effective in those cases because although there are a lot of temporary causes for a false positive to spike, there are fewer where it's persistent.