Figure 1.

Cohort flow chart demonstrating inclusion and exclusion criteria of subjects in the study. We evaluated subjects who underwent a severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) nucleic acid amplification test (NAAT) at Massachusetts General Hospital between March 3 and May 18, 2020 for inclusion in the false-negative test cohort. Subjects with only 1 negative NAAT, an initial positive NAAT at Massachusetts General Hospital (MGH), or documentation of ≥1 prior positive NAATs were not eligible. We excluded subjects with ≥1 repeat SARS-CoV-2 NAATs if all of their NAATs were negative, the initial negative and subsequent positive tests were >14 days apart, a history of symptoms could not be obtained, or 2 reviewers reached consensus that the subject’s discordant tests were performed across separate illness episodes. A total of 60 subjects were included in the false-negative NAAT cohort. *, Initial positive NAAT performed at an outside facility or performed before the study window.