TY - JOUR
T1 - Higher SARS-CoV-2 detection of oropharyngeal compared with nasopharyngeal or saliva specimen for molecular testing
T2 - a multicentre randomised comparative accuracy study
AU - Todsen, Tobias
AU - Tolsgaard, Martin G
AU - Benfield, Thomas
AU - Folke, Fredrik
AU - Jakobsen, Kathrine K
AU - Gredal, Niels Tobias
AU - Ersbøll, Annette K
AU - von Buchwald, Christian
AU - Kirkby, Nikolai
N1 - © Author(s) (or their employer(s)) 2023. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.
PY - 2023/10
Y1 - 2023/10
N2 - BACKGROUND: Testing is critical for detecting SARS-CoV-2 infection, but the best sampling method remains unclear.OBJECTIVES: To determine whether nasopharyngeal swab (NPS), oropharyngeal swab (OPS) or saliva specimen collection has the highest detection rate for SARS-CoV-2 molecular testing.METHODS: We conducted a randomised clinical trial at two COVID-19 outpatient test centres where NPS, OPS and saliva specimens were collected by healthcare workers in different orders for reverse transcriptase PCR testing. The SARS-CoV-2 detection rate was calculated as the number positive by a specific sampling method divided by the number in which any of the three sampling methods was positive. As secondary outcomes, test-related discomfort was measured with an 11-point numeric scale and cost-effectiveness was calculated.RESULTS: Among 23 102 adults completing the trial, 381 (1.65%) were SARS-CoV-2 positive. The SARS-CoV-2 detection rate was higher for OPSs, 78.7% (95% CI 74.3 to 82.7), compared with NPSs, 72.7% (95% CI 67.9 to 77.1) (p=0.049) and compared with saliva sampling, 61.9% (95% CI 56.9 to 66.8) (p<0.001). The discomfort score was highest for NPSs, at 5.76 (SD, 2.52), followed by OPSs, at 3.16 (SD 3.16) and saliva samples, at 1.03 (SD 18.8), p<0.001 between all measurements. Saliva specimens were associated with the lowest cost, and the incremental costs per detected SARS-CoV-2 infection for NPSs and OPSs were US$3258 and US$1832, respectively.CONCLUSIONS: OPSs were associated with higher SARS-CoV-2 detection and lower test-related discomfort than NPSs for SARS-CoV-2 testing. Saliva sampling had the lowest SARS-CoV-2 detection but was the least costly strategy for mass testing.TRIAL REGISTRATION NUMBER: NCT04715607.
AB - BACKGROUND: Testing is critical for detecting SARS-CoV-2 infection, but the best sampling method remains unclear.OBJECTIVES: To determine whether nasopharyngeal swab (NPS), oropharyngeal swab (OPS) or saliva specimen collection has the highest detection rate for SARS-CoV-2 molecular testing.METHODS: We conducted a randomised clinical trial at two COVID-19 outpatient test centres where NPS, OPS and saliva specimens were collected by healthcare workers in different orders for reverse transcriptase PCR testing. The SARS-CoV-2 detection rate was calculated as the number positive by a specific sampling method divided by the number in which any of the three sampling methods was positive. As secondary outcomes, test-related discomfort was measured with an 11-point numeric scale and cost-effectiveness was calculated.RESULTS: Among 23 102 adults completing the trial, 381 (1.65%) were SARS-CoV-2 positive. The SARS-CoV-2 detection rate was higher for OPSs, 78.7% (95% CI 74.3 to 82.7), compared with NPSs, 72.7% (95% CI 67.9 to 77.1) (p=0.049) and compared with saliva sampling, 61.9% (95% CI 56.9 to 66.8) (p<0.001). The discomfort score was highest for NPSs, at 5.76 (SD, 2.52), followed by OPSs, at 3.16 (SD 3.16) and saliva samples, at 1.03 (SD 18.8), p<0.001 between all measurements. Saliva specimens were associated with the lowest cost, and the incremental costs per detected SARS-CoV-2 infection for NPSs and OPSs were US$3258 and US$1832, respectively.CONCLUSIONS: OPSs were associated with higher SARS-CoV-2 detection and lower test-related discomfort than NPSs for SARS-CoV-2 testing. Saliva sampling had the lowest SARS-CoV-2 detection but was the least costly strategy for mass testing.TRIAL REGISTRATION NUMBER: NCT04715607.
KW - Adult
KW - COVID-19 Testing
KW - COVID-19/diagnosis
KW - Clinical Laboratory Techniques/methods
KW - Humans
KW - Nasopharynx
KW - SARS-CoV-2
KW - Saliva
KW - Specimen Handling/methods
U2 - 10.1136/thorax-2022-219599
DO - 10.1136/thorax-2022-219599
M3 - Journal article
C2 - 37208187
VL - 78
SP - 1028
EP - 1034
JO - Thorax
JF - Thorax
SN - 0040-6376
IS - 10
ER -