Obviously the United States needs lots and lots more testing for COVID-19 to determine who is and isn’t carrying it. Future years will look back with horror at the federal government’s failure to prepare during the first three months of this year for what everybody who paid attention knew what was coming.
But even if we had infinite supplies of material for testing and staff to do the work, we wouldn’t want to test everybody. And why not? Regular Granite Geek readers know why not: The false-positive/negative quandary.
I wrote about it last month as a theoretical exercise (and because I needed a quick column, to be honest). I never thought it would have such real-world implications.
You can read it again, if you’ve forgotten: “A 99% accurate test is wrong half the time.”