MR imaging vs. clinical critera according to the American College of Rheumatology
| Comparison | n | TP | TN | FP | FN | Sens | Spec | PPV | NPV |
|---|---|---|---|---|---|---|---|---|---|
| MR vs ACR (all patients) | 64 | 25 | 32 | 1 | 6 | 80.6 | 97.0 | 96.2 | 84.2 |
| MR vs ACR (<10 days of steroids) | 50 | 24 | 21 | 1 | 4 | 85.7 | 95.5 | 96.0 | 84.0 |
| MR vs ACR (>10 days) | 14 | 1 | 11 | 0 | 2 | 33.3 | 100 | 100 | 84.6 |
| Histo vs ACR | 32 | 21 | 5 | 0 | 6 | 77.8 | 100 | 100 | 45.5 |
| MR vs ACR (patients with histo) | 32 | 22 | 5 | 0 | 5 | 81.5 | 100 | 100 | 50.0 |
| MR vs histo | 32 | 19 | 8 | 3 | 2 | 90.5 | 72.7 | 86.4 | 80.0 |
| Wall thickness vs ACR (all patients) | 64 | 22 | 26 | 7 | 9 | 71.0 | 78.8 | 75.9 | 74.3 |
Note:—Results of the MR evaluation and temporal artery biopsy in the diagnosis of giant cell arteritis (GCA). The number of subjects (n), true-positive (TP), true-negative (TN), false-positive (FP), and false-negative (FN) cases, as well as the values for sensitivity (Sens), specificity (Spec), positive predictive value (PPV), and negative predictive value (NPV) are reported for all of the patients in the study and various subgroups. Histo indicates histology; ACR, American College of Rheumatology.