Reviewed by Cindy Noyes
Todsen and colleagues describe a multi-center randomized trial comparing the accuracy of self- and healthcare worker (HCW)-collected nasal and throat swabs for COVID-19 antigen testing. Conducted in Denmark from February 15 through March 25, 2022; four swabs were collected for each participant, one nasal and one throat for polymerase chain reaction (PCR) testing and then subjects were randomized to have HCW collected nasal and throat swabs or self-collected nasal and throat swabs for antigen testing. There were 2674 participants, 827 (30%) with positive PCR via nares, throat or both. When comparing PCR to antigen testing, the findings suggest that HCW-collected throat swabs had a higher sensitivity than HCW nasal specimens, while self-collected nasal swabs were no different than HCW collected nasal swabs. Importantly, combining throat and nasal specimens increased testing sensitivity in both self- and HCW- collected specimens significantly (15.5%; 21.4% respectively), suggesting that self-collected specimens are adequate and that accuracy in both circumstances could be increased by swabbing both nares and throat.
Todsen T, et al. COVID-19 rapid antigen tests with self-collected vs health care worker-collected nasal and throat swab specimens: a randomized clinical trial. JAMA Network Open. 2023; 6 (12): e2344295