Researchers are finding that COVID-19 testing has roughly 33% false negatives: https://www.wsj.com/articles/questions-about-accuracy-of-coronavirus-tests-sow-wo

Researchers are finding that COVID-19 testing has roughly 33% false negatives: https://www.wsj.com/articles/questions-about-accuracy-of-coronavirus-tests-sow-worry-11585836001?mod=e2tw https://www.wsj.com/articles/questions-about-accuracy-of-cor... The LabCorp test is not FDA cleared or approved and is being used under an emergency act. "Testing was performed using the cobas(R) SARS-CoV-2 test. This test was developed and its performance characteristics determined by LabCorp Laboratories. This test has not been FDA cleared or approved. This test has been authorized by FDA under an Emergency Use Authorization (EUA). This test is only authorized for the duration of time the declaration that circumstances exist justifying the authorization of the emergency use of in vitro diagnostic tests for detection of SARS-CoV-2 virus and/or diagnosis of COVID-19 infection under section 564(b)(1) of the Act, 21 U.S.C. 360bbb-3(b)(1), unless the authorization is terminated or revoked sooner." The Quest test is not FDA approved either: https://www.questdiagnostics.com/dms/Documents/covid-19/SARSCoV-2_Patient_Fact_Sheet.pdf https://www.questdiagnostics.com/dms/Documents/covid-19/SARS... "It is possible for this test to give a negative result that is incorrect (false negative) in some people with COVID-19. This means that you could possibly still have COVID-19 even though the test is negative." "This test is not yet approved or cleared or authorized by the United States Food and Drug Administration (FDA)." Due to this, it's hard to trust test results. It's a best effort and not perfect.