A Bayesian analysis of strategies to rule out COVID19 using reverse transcriptase-polymerase chain reaction (RT-PCR).

To the Editor.—The coronavirus disease 2019 (COVID-19) pandemic may overwhelm health care capacity in parts of the United States and United Kingdom in the coming months. Erroneously ruling out COVID-19 based on a false-negative diagnostic test poses a public health hazard. The probability of such an error is quantified by the false omission rate (FOR). The FOR 1⁄4 false negatives/(true negativesþ false negatives), and this value depends on the prevalence of disease and operating characteristics of the diagnostic test. Preliminary data suggest the sensitivity of the COVID-19 reverse transcriptase–polymerase chain reaction (RT-PCR) may be 70% for nasopharyngeal (NP) and sputum samples, and 90% for bronchoalveolar lavage (BAL). We examined strategies to rule out COVID-19 by RT-PCR with an acceptably low FOR in hospitalized patients suspected of having COVID-19.