Why does blood test results show false-positive and what does it mean, is it good bad or otherwise?

Answer:
Usually it's good.
False positive means that the test made an error: you tested "positive" for something (maybe a disease), but the result was false. In other words, you don't have the disease.
For example, if you're not pregnant, but a test says "pregnant", that's a false positive.
If you don't have cancer, but the test says you have cancer, the test is wrong. That's another false positive.
If you're looking for a friend in a crowd, and you think you see them, but it;s just a stranger, well, that's a false positive too.Almost all tests give some false positives. It's so hard to design the perfect test.
When they make medical tests, they know the test won't be perfect. They'd rather have false positives than miss someone with a serious illness (false negative), so tests are usually biased to false positives.
That way, the worst that happens is that someone who is healthy gets a bit of a scare, but then is told that everything is okay.
Missing an illness that is actually there is much worse.
You got a false positive? Good.

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Well, it depends on which test, of course, but a lot of things cause false positives in lab tests, which is why a positive result for just about anything is usually rerun on another kind of test. A false positive is usually not good or bad, it's just not a big deal, unless the false positive is caused by some other problem, but that's pretty uncommon.

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Depending on the accuracy and profiecy of the laboratory and the testing protocol, false positives may occur for several reasons.1) antibodies sometimes falsely produce positive results on other tests.2) The test is really inaccurate 3) It may not actually be a false positive. In some cases such as Lyme disease, if you are in an area not considered "endemic" by the state physician they may say it is false positive when in fact it may be true positive! or False negative!!If you are concerned about Tick borne illnesses, please check with your local advocacy for your state or the national advocacy groups to see if your area or an area you have been to has the tick illness in question.If it is other illness, check with the advocacy group for that illness to find out how accurate and which test protocols to use.

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