Table 3.
Sensitivity and specificity of biomarkers
| Biomarker | Flare definition | Sensitivity | Specificity | PPV | NPV |
| HER2 | R-SLEDAI | 24% | 77% | 69% | 32% |
| HER2 | Creatinine | 27% | 77% | 42% | 62% |
| TWEAK | R-SLEDAI | 43% | 66% | 71% | 38% |
| TWEAK | Creatinine | 40% | 66% | 43% | 63% |
| VCAM-1 | R-SLEDAI | 38% | 74% | 74% | 38% |
| VCAM-1 | Creatinine | 30% | 74% | 43% | 62% |
| All three biomarkers | R-SLEDAI | 18% | 94% | 86% | 36% |
| All three biomarkers | Creatinine | 20% | 94% | 67% | 65% |
HER2, human epidermal growth factor receptor 2; NPV, negative predictive value; PPV, positive predictive value; R-SLEDAI, renal Systemic Lupus Erythematosus Disease Activity Index; TWEAK, tumour necrosis factor-like weak inducer of apoptosis; VCAM-1, vascular cell adhesion molecule-1.