Table 2.
Sensitivity, specificity, PPV, NPV and accuracy of entheseal ultrasound and serum COMP in the preclinical diagnosis of psoriatic arthritis.
| Entheseal ultrasound | Serum COMP | |
|---|---|---|
| True positive cases (psoriatic arthritis patients with positive test) (N) | 14 | 26 |
| True negative cases (psoriatic patients with negative test) (N) | 20 | 8 |
| False positive cases (psoriatic patients with positive test) (N) | 10 | 22 |
| False negative cases (psoriatic arthritis patients with negative test) (N) | 16 | 4 |
| Sensitivity (%) | 47% | 87% |
| Specificity (%) | 67% | 27% |
| PPV (%) | 58.3% | 54% |
| NPV (%) | 55.6% | 66.7% |
| Accuracy (%) | 56.8% | 56.8% |
Abbreviations: PPV, Positive predictive value; NPV, Negative predictive value.