Fig. 1.

Standards for Reporting of Diagnostic Accuracy Studies (STARD) diagram of participant flow through the validation of LFA for identification of SARS-CoV-2 antibodies in serum samples; reference standard RT-qPCR for SARS-CoV-2 on nasopharyngeal swabs and clinical, epidemiology, and radiologic criteria [3]. ^aParticipants who tested RT-qPCR negative for SARS-CoV-2 on nasopharyngeal samples. ^bParticipants were not tested for SARS-CoV-2 by RT-qPCR as the samples were taken before the emergence of the virus in China. LFA, lateral flow immunochromatographic assay.