For COVID-19 testing, higher negative predictive value is more important than higher positive predictive value to prevent infected individuals from unknowingly spreading the virus.

“I would argue in this case negative predictive value is the most important thing why so what is negative predictive value by the way negative predictive value is the true negatives divided by the negatives times the false negatives of any given test so obviously the fewer false negatives you have the more that number approaches one the same is true for positive predictive value it's the true positives over the total positives pardon me the well the total positives the false positives plus the true true positives false positive the true positive and again as that approach is one it's telling you that your false positives or approach is zero but let's go back to this true negative issue why is negative predictive value important in a test like this you don't want somebody who has the virus to test negative because what is that person gonna do they're gonna go right back out and infect other people unknowingly so if you're gonna err on the side of one of these tests you'll take higher negative predictive value over higher positive predictive value”