False positive math

[jeepyj]

I can't wrap my head around the weird math here. Can somebody explain this for a retard?


A test that has a 99% specificity is still wrong 1% of the time. And if it's being used to test a population where 1% of people are infected, half the time a positive result will be a false positive.


https://www.npr.org/sections/health-...prove-accuracy


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[Wildcat]

That's not math, it's stupid.
The test will still only give a 1% false positive rate no mater what percentage of the population you test.