Table 2.
Sensitivity and specificity of the self-testing compared with quantitative RT-PCR, quantitative RT-PCR with a Ct-value below the cut-off and to the composite reference standard
| Sensitivity (95% CI) |
Specificity (95% CI) |
|||||
|---|---|---|---|---|---|---|
| Overall | BD-RDT | Roche-RDT | Overall | BD-RDT | Roche-RDT | |
| qRT-PCR pos. or neg. | 55.6% (50.5%–60.7%) | 49.1% (41.7%–56.5%) | 61.5% (54.6%–68.3%) | 99.8% (99.6%–99.9%) | 99.9% (99.7%–100%) | 99.7% (99.4%–99.9%) |
| qRT-PCR, Ct-value < cutoffa | 78.4% (73.2%–83.5%) | 76.1% (68.1%–84.1%) | 80.1% (73.4%–86.9%) | 99.4% (99.1%–99.7%) | 99.7% (99.4%–99.9%) | 99.1% (98.6%–99.6%) |
| Composite reference standardb | 77.2% (71.3%–83.1%) | 75.9% (66.7%–85.1%) | 78.8% (70.5%–85.8%) | 99.8% (99.6%–99.9%) | 99.9% (99.7%–100.0%) | 99.7% (99.4%–99.9%) |
Abbreviations: BD-RDT, BD Veritor System for Rapid Detection of SARS-CoV-2 (Becton Dickinson, Franklin Lakes, NJ, USA); COVID-19, coronavirus disease 2019; IQR, interquartile range; neg.: negative; pos., positive (Ct-value <45.0); qRT-PCR, quantitative RT-PCR; RDT, rapid antigen detection test; Roche-RDT, Roche SARS-CoV-2 antigen detection test (Roche, Basel, Switzerland).
Ct-value below which the chance of a positive culture was larger than 0.5 (Alinity assay: 23.0; Laboratory-developed assay 24.5).
Composite reference standard was defined as positive when having a positive result in at least two out of the following three tests: viral culture, qRT-PCR and RDT.