The Buzz | Accuracy still unknown for many coronavirus tests rushed out

How accurate are the coronavirus tests used in the U.S.?
Months into the outbreak, no one really knows how well many of the screening tests work, and experts at top medical centers say it is time to do the studies to find out.
When the new virus began spreading, the Food and Drug Administration used its emergency powers to OK scores of quickly devised tests, based mainly on a small number of lab studies showing they could successfully detect the virus.
That’s very different from the large patient studies that can take weeks or months, which experts say are needed to provide a true sense of testing accuracy.
The FDA’s speedy response came after it was initially criticized for delaying the launch of new tests during a crisis and after the Centers for Disease Control and Prevention stumbled in getting its own test out to states.
In recent weeks, preliminary findings have flagged potential problems with some COVID-19 tests, including one used daily at the White House. Faulty tests could leave many thousands of Americans with the incorrect assumption that they are virus-free, contributing to new flare-ups of the disease as communities reopen.