Table 1.
- Subgroup analysis of ethnicity, saliva collection method, and participants’ symptoms.
| Subgroup | Study (n) | DOR | Sensitivity | Specificity | AUC | NPV | PPV |
|---|---|---|---|---|---|---|---|
| 95% CIs | |||||||
| I2 | |||||||
| Self-collected saliva (total) | 41 | 196.2022 | 0.8476 | 0.9817 | 0.955 | 0.9467 | 0.9404 |
| [117.8833-326.5546] | [0.8045-0.8826] | [0.9707-0.9887] | [0.9130-0.9678] | [0.9122-0.9599] | |||
| 82% | 87.3% | 89% | 96.4% | 83.2% | |||
| Regions | |||||||
| North America | 20 | 250.4321 | 0.8798 | 0.9807 | 0.9635 | 0.9275 | |
| [120.4677-520.6066] | [0.8182-0.9224] | [0.9646-0.9896] | [0.9265-0.9822] | [0.8801-0.9571] | |||
| 81.1% | 84.5% | 87.2% | 94.1% | 81.1% | |||
| Asia | 12 | 92.3075 | 0.7938 | 0.9766 | 0.9283 | 0.9175 | |
| [35.8172-237.8934] | [0.6970-0.8656] | [0.9297-0.9924] | [0.8056-0.9759] | [0.8410-0.9589] | |||
| 85.6% | 87.1% | 94.7% | 0.9283 [0.8056-0.9759] | 0.9175 [0.8410-0.9589] | |||
| Europe | 6 | 212.1821 | 0.8080 | 0.9852 | 0.9143 | 0.9676 | |
| [117.6169-382.7785] | [0.6984-0.8844] | [0.9751-0.9912] | [0.7872-0.9685] | [0.9369-0.9836] | |||
| 0% | 82.4% | 0% | 95% | 30.9% | |||
| South America | 2 | 748.1044 | 0.8814 | 0.9924 | 0.9189 | 0.9839 | |
| [171.1188-3270.5945] | [0.7180-0.9559] | [0.9321-0.9992] | [0.8642-0.9527] | [0.9378-0.9960] | |||
| 0% | 71.2% | 35.1% | 5.2% | 0% | |||
| Oceania | 1 | 269.5000 | 0.8462 | 0.9800 | 0.8909 | 0.9706 | |
| [31.0018-2342.7756] | [0.6974-0.9292] | [0.8712-0.9972] | [0.7777-0.9502] | [0.8186-0.9959] | |||
| NA | NA | NA | NA | NA | |||
| P-value | 0.1979 | 0.389 | 0.8652 | 0.2833 | 0.079 | ||
| Collection method | |||||||
| Only oral cavity saliva | 26 | 215.1566 | 0.8365 | 0.9827 | 0.9496 | 0.9367 | |
| [110.2014-420.0706] | [0.7793-0.8812] | [0.9713-0.9896] | [0.9111-0.9719] | [0.9007-0.9602] | |||
| 84% | 87.4% | 84.4% | 96.1% | 80.9% | |||
| Only oral cavity saliva (not defined) | 8 | 237.4246 | 0.8919 | 0.9820 | 0.9731 | 0.9173 | |
| [61.4927-916.7010] | [0.8432-0.9268] | [0.9035-0.9969] | [0.9269-0.9904] | [0.7993-0.9686] | |||
| 85.2% | 28.7% | 96.3% | 89.7% | 86.0% | |||
| Enhanced saliva | 7 | 127.2254 | 0.8353 | 0.9779 | 0.8823 | 0.9654 | |
| [41.0992-393.8348] | [0.6844-0.9222] | [0.9338-0.9928] | [0.6404-0.9693] | [0.9075-0.9875] | |||
| 67.0% | 91.7% | 75.7% | 2.0842 | 70.9% | |||
| P-value | 0.7001 | 0.2282 | 0.928 | 0.2176 | 0.4355 | ||
| Patient symptom | |||||||
| Symptomatic | 22 | 245.6222 | 0.8851 | 0.9791 | 0.9522 | 0.9495 | |
| [111.2860-542.1192] | [0.8497-0.9130] | [0.9580-0.9898] | [0.9124-0.9744] | [0.9103-0.9721] | |||
| 80.6% | 71.0% | 87.3% | 92.2% | 80.3% | |||
| Mixed | 15 | 159.4638 | 0.8208 | 0.9783 | 0.9164 | 0.9435 | |
| [72.7019-349.7664] | [0.7399-0.8806] | [0.9588-0.9886] | [0.8313-0.9606] | [0.9003-0.9687] | |||
| 83.4% | 90.7% | 85.6% | 97.0% | 82.4% | |||
| Asymptomatic | 4 | 184.8991 | 0.7049 | 0.9933 | 0.9772 | 0.8483 | |
| [44.5856-766.7872] | [0.4705-0.8653] | [0.9673-0.9987] | [0.8563-0.9968] | [0.6869-0.9345] | |||
| 80.3% | 82.3% | 92.3% | 97.0% | 71.2% | |||
| P-value | 0.7469 | 0.03 | 0.3924 | 0.329 | 0.0879 | ||
DOR: diagnostic odds ratio, CI: confidence interval, AUC: area under the curve, NPV: negative predictive value, PPV: positive predictive value