The study of sensitivity, specificity and accuracy of Antigen Test Kits (ATK) compare with Real time RT-PCR for Coronavirus 2019 at Coronavirus 2019’s field screening service

Abstract

COVID-19 has become an essential problem until currently. It is still spreading in community and other public areas. Active case finding is an important method to indicate infected cases and deliver them to treat for stopping mode of transmission of SAR-CoV-2. Therefore, ministry of public health announced the policy using ATK for fast screen test to control COVID-19 effectively. This article is descriptive design focusing on those who had Antigen Test Kits (ATK) positive result compare with confirmed real time RT-PCR of SAR-CoV-2. All case groups were suspected, probable, confirmed including close contact cases who visited at Rajamangala National Stadium and Thupatemi Royal Thai Air Force Sports Stadium during 22nd -28th July 2021 for 2,445 cases.

Sampling had both ATK and Real time RT-PCR results with false negative 82 cases (11.5%), false positive 23 cases (1.34%). The incubation period is between 0 to 14 days and median of 5 days. Sensitivity specificity and accuracy are as follow: Antigen Test Kits (ATK) 95.36% (95%CI, 91.06 to 96.96) 96.60% (95%CI, 93.26 to 97.56) and 96.64% (95%CI, 93.44 to 99.84) . Positive predictive value (PPV) = 98% (95%CI, 90.00 to 100.00) and Negative predictive value (NPV) = 88% (95%CI, 80.00 to 96.00) at prevalence 10% of SAR-CoV-2.

This study showed that Antigen Test Kits (ATK) have significant effective result to use in active case finding in high prevalence area. However, in high risk group cases who had negative ATK result need conform to Real time RT-PCR for the utmost outcome controlling the spreading of COVID-19.