False positives in RT PCR

Cohen discovered that false positives were actually fairly common. The best labs reported few if any, but other labs reported up to 8% of their positive results were false positives. The average was around 2% false positive.

With 0.1% false positives, 99.9 % specificity, 14 of 15 positive tests are false positives when the rate of infection is as low as Autralia or Norway. 

In principle with 7% false positives, the whole epidemic in the US could be false positives. And we don’t know since there is no gold standard. 

 


https://www.npr.org/sections/health-shots/2020/06/15/871186164/what-zebra-mussels-can-tell-us-about-errors-in-coronavirus-tests?t=1595631313782

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