USING PRE-TEST PROBABILITIES TO MORE EFFECTIVELY UTILIZE POINT-OF-CARE COVID-19 TESTING IN NURSING HOMES

Nursing home residents are at increased risk of contracting severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative infectious agent of COVID19, as a result of exposure to asymptomatic or pre-symptomatic health care workers. In an effort to reopen nursing homes safely, federal agencies have proposed guidelines for testing of staff and residents at regular intervals. To mitigate testing shortages, facilities received antigen point-of-care (POC) testing devices for COVID-19 but without clear guidance on when to select an antigen vs. molecular based test and how to act on a positive or negative test result. This special article presents an algorithm for how to approach pre-test probability in the selection of a certain test and how to use post-test probability to act on a test result in the context of risk mitigation.