Diagnostic performance of GenBody COVID-19 rapid antigen test for laboratory and non-laboratory medical professionals in real practice: A retrospective study

Point-of-care tests for coronavirus disease 2019 (COVID-19) antigen detection have been widely used for rapid diagnosis in various settings. However, research on the diagnostic performance of the COVID-19 antigen test performed by non-laboratory personnel is limited. In this study, we aimed to elucidate the diagnostic performance of GenBody COVID-19 rapid antigen between laboratory professionals and non-laboratory staff. We retrospectively analyzed the data of patients who underwent both GenBody COVID-19 rapid antigen testing and reverse transcription polymerase chain reaction (RT-PCR) between November 01, 2021, and June 30, 2022. The diagnostic performance of the antigen test was compared between laboratory and non-laboratory operators, using RT-PCR as the gold standard. Sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio, positive predictive value, negative predictive value, and accuracy were calculated and sensitivity analysis was performed based on the PCR cycle threshold (Ct) value. Of the 11,963 patients, 1273 (10.6%) tested positive using real-time RT-PCR. The sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio, positive predictive value, negative predictive value, and accuracy of the GenBody COVID-19 rapid antigen test with 95% confidence interval were 79.92% (77.26%-82.39%), 99.23% (98.73%-99.57%), 103.25 (62.31-171.11), 0.2 (0.18-0.23), 510.18 (299.81-868.18), 98.11% (96.91%-98.85%), 90.75% (89.64%-91.75%) and 92.76% (91.76%-93.67%), respectively, for non-laboratory staff and 79.80% (74.78%-84.22%), 99.99% (99.94%-100.00%), 6983.92 (983.03-49617.00), 0.2 (0.16-0.25), 34566.45 (4770.30-250474.46) 99.58% (97.09%-99.94%), 99.32% (99.15%-99.46%), and 99.33% (99.13%-99.48%), respectively, for laboratory staff. Notably, when the PCR Ct value exceeded 25, the sensitivity of both the groups decreased to < 40%. The diagnostic performance of GenBody COVID-19 rapid antigen performed by non-laboratory staff was comparable to that of laboratory professionals. However, it should be noted that the sensitivity of the antigen tests decreased when the PCR Ct value exceeded 25. Overall, the GenBody COVID-19 antigen test is a viable option for non-laboratory staff during an epidemic.