False Negatives Raise More Questions About Virus Test Accuracy

New research is raising more questions about tests used around the U.S. to diagnose Covid-19 patients, with some of the tests producing a surprisingly high rate of false negatives that incorrectly show a person isn’t infected.

One study released Wednesday examining an Abbott Laboratories test that’s used at the White House to get rapid diagnoses indicated it may miss as many as half of positive cases. A second peer-reviewed study released hours later suggested that results for another type of widely used diagnostic test are particularly unreliable early on in an infection.

The first study found that Abbott’s ID NOW ...