4 ms·

What is the false positive rates of this, if 10k people are tested everyday, can we expect 100 false positive everyday?

• killjoywashere 7y ago
  PCR tends to have great specificity and great in vitro sensitivity. The sensitivity drops off with pre-analytic errors that accumulate in real world testing (wrong collection method, wrong media, wrong swab, etc). So false negatives are the problem. The nice thing is that it catches acute infections even earlier than IgM.
• vikramkr 7y ago
  PCR tends to have pretty low false positive rates if used properly - so from a technology perspective the contribution to that would be low. Although, if they're using more innovative PCR methods, maybe there's a risk. Where I think there's room for them to introduce false positive rates (that we would not know without having access to proprietary information) is in how they design something called a primer sequence. this is a little bit of DNA that will go and find to a different little bit of DNA that's part of a larger bit of DNA. Basically it lets you target it a little bit of DNA within a larger bit of DNA. you want to make this primer so that it only will bind to coronavirus DNA but will not bind to any other DNA. It's important to design it that way because in PCR the DNA that amplifies to give you the signal is whatever that primer was able to bind it to. If you accidentally make a primer that can bind to some non coronavirus DNA (something we call off Target binding) then you would end up with false positives. There are bioinformatics tools to evaluate this and presumably the FDA and the company did some work into making sure they didn't make any mistakes when designing that, but that's what I think of first when it comes to false positives.