Clinical Performance of the Standard Q COVID-19 Rapid Antigen Test and Simulation of its Real-World Application in Korea

• Published in: Annals of laboratory medicine 2021, 41(6), , pp.588-592
• Main Authors: Lee, Jaehyeon, Kim, So Yeon, Huh, Hee Jae, Kim, Namsu, Sung, Heungsup, Lee, Hyukmin, Roh, Kyoung Ho, Kim, Taek Soo, Hong, Ki Ho
• Format: Article
• Language: English
• Subjects: Brief Communications; 병리학
• ISSN: 2234-3806; 2234-3814
• DOI: 10.3343/alm.2021.41.6.588

The rapid antigen test (RAT) for coronavirus disease (COVID-19) represents a potent diagnostic method in situations of limited molecular testing resources. However, considerable performance variance has been reported with the RAT. We evaluated the clinical performance of Standard Q COVID-19 RAT (SQ-RAT; SD Biosensor, Suwon, Korea), the first RAT approved by the Korean Ministry of Food and Drug Safety. In total, 680 nasopharyngeal swabs previously tested using real-time reverse-transcription PCR (rRT-PCR) were retested using SQ-RAT. The clinical sensitivity of SQ-RAT relative to that of rRT-PCR was 28.7% for all specimens and was 81.4% for specimens with RNA-dependent RNA polymerase gene ( RdRp ) threshold cycle (Ct) values ≤23.37, which is the limit of detection of SQ-RAT. The specificity was 100%. The clinical sensitivity of SQ-RAT for COVID-19 diagnosis was assessed based on the Ct distribution at diagnosis of 33,294 COVID-19 cases in Korea extracted from the laboratory surveillance system of Korean Society for Laboratory Medicine. The clinical sensitivity of SQ-RAT for COVID-19 diagnosis in the Korean population was 41.8%. Considering the molecular testing capacity in Korea, use of the RAT for COVID-19 diagnosis appears to be limited.