I thought the PCR tests in Asia had a specificity of around 70% which is why they needed two positive tests in a row (or two negative tests in a row to confirm the patient had recovered).
(ie, if an individual is infected does it detect it 70% of the time? Or just a true negative 70% of the time? What about the chance of a false negative? A false positive? Etc)
TN/(TN+FP)
https://en.m.wikipedia.org/wiki/Sensitivity_and_specificity#...