PT - JOURNAL ARTICLE AU - Nicole Ngai Yung Tsang AU - Hau Chi So AU - Benjamin J. Cowling AU - Gabriel M. Leung AU - Dennis Kai Ming Ip TI - Performance of saline and water gargling for SARS-CoV-2 reverse transcriptase PCR testing: a systematic review and meta-analysis AID - 10.1183/16000617.0014-2022 DP - 2022 Sep 30 TA - European Respiratory Review PG - 220014 VI - 31 IP - 165 4099 - http://err.ersjournals.com/content/31/165/220014.short 4100 - http://err.ersjournals.com/content/31/165/220014.full SO - EUROPEAN RESPIRATORY REVIEW2022 Sep 30; 31 AB - The performance of gargling for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) reverse transcriptase (RT)-PCR testing has not been previously reviewed. This review systematically assessed the performance of saline and water gargling for SARS-CoV-2 RT-PCR testing in the settings of diagnosing and monitoring viral shedding.We included original studies comparing the performance of gargling and (oropharyngeal–)nasopharyngeal swabs for SARS-CoV-2 RT-PCR testing. Studies conducted in either suspected individuals or confirmed cases were included and analysed separately. The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were examined using random-effects models.Gargles achieved a high overall sensitivity (91%), specificity (97%), PPV (95%) and NPV (91%) for SARS-CoV-2 RT-PCR testing. Studies using saline gargle and water gargle have an overall sensitivity of 97% and 86%, respectively. The sensitivity values were largely maintained for saline and water gargling on stratified analysis, for both diagnosis (96% and 92%) and viral shedding monitoring (98% and 78%). A higher sensitivity was also reported by studies using sterile saline (100%), a smaller amount of gargling solution (92% versus 87%) and a longer gargling duration (95% versus 86%).Our results supported the use of gargling as a sampling approach for SARS-CoV-2 RT-PCR testing, which achieved a high sensitivity for both diagnosis and viral shedding monitoring purposes. Further investigation on the comparative performance of different gargling mediums is needed to draw a definitive conclusion.Gargling is a reliable sampling approach for SARS-CoV-2 RT-PCR test. Results suggest potential differential performance in factors including the nature, sterility and volume of gargling medium, and duration of gargling, which need further exploration. https://bit.ly/3tYau81