Diagnostic performance of 5 cut-off levels of anti-cyclic citrullinated peptide test for the diagnosis of rheumatoid arthritis.
| Level (U/ml) | |||||
|---|---|---|---|---|---|
| > 1 | > 2 | > 3 | > 4 | > 5 | |
| Sensitivity (%) | 91 | 86 | 83 | 82 | 80 |
| Specificity (%) | 46 | 68 | 74 | 78 | 82 |
| PPV (%) | 44 | 55 | 59 | 63 | 67 |
| NPV (%) | 91 | 91 | 91 | 90 | 90 |
| PLR | 1.69 | 2.71 | 3.20 | 3.74 | 4.35 |
| NLR | 4.88 | 4.78 | 4.45 | 4.26 | 4.10 |
PPV: positive predictive value, NPV: negative predictive value, PLR: positive likelihood ratio, NLR: negative likelihood ratio.