Table 5.
Diagnostic performance of laboratory indicators in patients with COVID-19
| Model | AUC (95% CI) | SE | P value | Cut-off | Sensitivity | Specificity | Youden index |
| Severe patients | |||||||
| C reactive protein | 0.856 (0.813 to 0.898) | 0.022 | <0.001 | 40.5 | 0.723 | 0.846 | 0.569 |
| Neutrophil count | 0.787 (0.744 to 0.831) | 0.022 | <0.001 | 4.24 | 0.687 | 0.810 | 0.497 |
| Serum amyloid A | 0.658 (0.582 to 0.733) | 0.038 | <0.001 | 34.96 | 1.000 | 0.413 | 0.413 |
| Erythrocyte sedimentation rate | 0.756 (0.683 to 0.829) | 0.037 | <0.001 | 23.84 | 0.782 | 0.687 | 0.469 |
| NLR | 0.861 (0.816 to 0.906) | 0.023 | <0.001 | 4.65 | 0.777 | 0.842 | 0.619 |
| PLR | 0.694 (0.645 to 0.743) | 0.025 | <0.001 | 239.65 | 0.545 | 0.684 | 0.229 |
| SII | 0.789 (0.747 to 0.832) | 0.022 | <0.001 | 969.35 | 0.650 | 0.828 | 0.478 |
| White cell count | 0.721 (0.673 to 0.769) | 0.024 | <0.001 | 6.79 | 0.555 | 0.827 | 0.382 |
| Prothrombin time | 0.730 (0.682 to 0.778) | 0.025 | <0.001 | 13.3 | 0.503 | 0.841 | 0.344 |
| Acivated partial thromboplastin time | 0.425 (0.367 to 0.482) | 0.029 | 0.007 | 40.15 | 0.067 | 0.983 | 0.050 |
| Thrombin time | 0.464 (0.409 to 0.519) | 0.028 | 0.203 | 16.95 | 0.105 | 0.940 | 0.045 |
| Fibrinogen | 0.687 (0.636 to 0.738) | 0.026 | <0.001 | 3.77 | 0.646 | 0.679 | 0.325 |
| D-dimer | 0.819 (0.769 to 0.869) | 0.025 | <0.001 | 0.335 | 0.723 | 0.804 | 0.527 |
| CPR+NLR+D-dimer | 0.894 (0.857 to 0.931) | 0.019 | <0.001 | 0.26 | 0.786 | 0.863 | 0.649 |
| Death of patients | |||||||
| C reactive protein | 0.865 (0.806 to 0.923) | 0.030 | <0.001 | 63.3 | 0.743 | 0.842 | 0.585 |
| Neutrophil count | 0.782 (0.710 to 0.853) | 0.036 | <0.001 | 4.53 | 0.768 | 0.731 | 0.499 |
| Serum amyloid A | 0.606 (0.505 to 0.708) | 0.052 | 0.237 | 50.47 | 0.857 | 0.583 | 0.440 |
| Erythrocyte sedimentation rate | 0.738 (0.619 to 0.858) | 0.061 | 0.002 | 33.50 | 0.688 | 0.741 | 0.429 |
| NLR | 0.894 (0.832 to 0.956) | 0.032 | <0.001 | 7.10 | 0.914 | 0.830 | 0.744 |
| PLR | 0.618 (0.538 to 0.699) | 0.041 | 0.004 | 244.15 | 0.567 | 0.786 | 0.353 |
| SII | 0.752 (0.679 to 0.824) | 0.037 | <0.001 | 1171.40 | 0.691 | 0.770 | 0.461 |
| White cell count | 0.723 (0.643 to 0.803) | 0.041 | <0.001 | 7.46 | 0.571 | 0.808 | 0.379 |
| Prothrombin time | 0.728 (0.652 to 0.804) | 0.039 | <0.001 | 13.3 | 0.615 | 0.761 | 0.376 |
| Acivated partial thromboplastin time | 0.360 (0.275 to 0.445) | 0.043 | <0.001 | 42.70 | 0.020 | 0.988 | 0.008 |
| Thrombin time | 0.554 (0.465 to 0.644) | 0.046 | <0.001 | 17.05 | 0.240 | 0.952 | 0.192 |
| Fibrinogen | 0.545 (0.461 to 0.629) | 0.043 | 0.295 | 3.32 | 0.667 | 0.451 | 0.118 |
| D-dimer | 0.872 (0.810 to 0.934) | 0.032 | <0.001 | 0.393 | 0.886 | 0.726 | 0.612 |
| CPR+NLR+D-dimer | 0.918 (0.873 to 0.962) | 0.023 | <0.001 | 0.07 | 0.914 | 0.823 | 0.737 |
Receiver operating characteristic curve and AUC were carried out to evaluate the value of laboratory indicators predicting severe disease and death of COVID-19. P<0.05 was considered statistically significant.
AUC, area under the receiver operating characteristic curve; NLR, neutrophil-to-lymphocyte ratio; PLR, platelet to lymphocyte ratio; SII, systemic immune-inflammation index.