thread Why antibody testing for immunity is problematic
permalink I thought the reported accuracy of the Roche test
makes the false positive rate only around 4%
permalink in the given example
that drops the total number of false positives from 49500 to 39600, which is still 80% of the positive results being incorrect
permalink Roche is claiming 100% sensitivity and 99.8% specificity
which will obviously remain to be verified, but at those numbers the false positive rate is single figure % depending on prevalence

our learned doctor friend is correct, we haven't made use of tests available to date because Bayesian stats magnify any inaccuracy, but the tests we're talking about now are accurate/specific to the point where that is an acceptable/useful level - particularly if they are generating an extremely small number of false negatives, which are obviously more important
permalink And that's
permalink now we just have to hope
that the antibody detected actually grants immunity
permalink And that most people actually create specific immunity following infection.
It's a hard one.