Investigation of the diagnostic performance of the SARS-CoV-2 saliva antigen test: A meta-analysis

Background: The COVID-19 pandemic is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Rapid identification and isolation of patients with COVID-19 are critical strategies to contain COVID-19. The saliva antigen test has the advantages of noninvasiveness and decreased transmission risk to health-care professionals. This meta-analysis investigated the diagnostic accuracy of the saliva antigen test for SARS-CoV-2. Methods: We searched for relevant studies in PubMed, Embase, Cochrane Library, and Biomed Central. Studies evaluating the diagnostic accuracy of saliva antigen tests for SARS-CoV-2 were included. The data of the included studies were used to construct a 2 × 2 table on a per patient basis. The overall sensitivity and specificity of saliva antigen tests were determined using a bivariate random-effects model. Results: Nine studies enrolling 9842 patients were included. The meta-analysis generated a pooled sensitivity of 65.3% and a pooled specificity of 99.7%. A subgroup analysis of the studies performing the chemiluminescent enzyme immunoassay (CLEIA) for participants from airports and public health centers revealed a pooled sensitivity of 93.6%. Conclusion: Our findings demonstrated that the saliva antigen test performed using CLEIA exhibited higher sensitivity for the detection of SARS-CoV-2. Therefore, the saliva antigen test performed using CLEIA might be an effective and noninvasive screening tool for SARS-CoV-2.