| Sacroiliitis positive (N=130) | Sacroiliitis negative (N=196) | Univariable analysis | Multivariable analysis | Diagnostic utility measures | ||||||
|---|---|---|---|---|---|---|---|---|---|---|
| N (%) | N (%) | OR | OR | Sen | Spe | PPV | NPV | LR+ | LR− | |
| A: Individual Characteristic of IBP | ||||||||||
| Morn. Stiff >30 min | 89 (68.5) | 106 (54.1) | 1.84* | 1.30 | 68.5 | 45.9 | 45.6 | 68.7 | 1.27 | 0.69 |
| Improve with exercise, not with rest | 41 (31.5) | 56 (28.6) | 1.15 | 31.5 | 71.4 | 42.3 | 61.1 | 1.10 | 0.04 | |
| Alter. buttock pain | 62 (47.7) | 36 (18.4) | 4.05** | 3.43** | 47.7 | 81.6 | 63.3 | 70.2 | 2.59 | 0.64 |
| Insidious onset | 114 (87.7) | 142 (72.4) | 2.71** | 2.15* | 87.7 | 27.6 | 44.5 | 77.1 | 1.21 | 0.44 |
| Awake 2nd half night | 84 (64.6) | 85 (43.4) | 2.39** | 1.71* | 64.6 | 56.6 | 49.7 | 70.7 | 1.49 | 0.63 |
| Response to NSAIDs | 90 (69.2) | 110 (56.1) | 1.76* | 1.32 | 69.2 | 43.9 | 45.0 | 68.3 | 1.23 | 0.70 |
| B: Combination of IBP characteristics | ||||||||||
| Calin criteria | 67 (51.5) | 57 (29.1) | 2.59** | – | 51.5 | 70.9 | 54.0 | 68.8 | 1.77 | 0.68 |
| Berlin criteria | 94 (72.3) | 97 (49.5) | 2.67** | – | 72.3 | 50.5 | 49.2 | 73.3 | 1.46 | 0.55 |
| ASAS criteria | 62 (47.7) | 45 (23.0) | 3.06** | – | 47.7 | 77.0 | 57.9 | 68.9 | 1.45 | 0.67 |
| Night + Insidious + Buttock (2/3) | 52 (40.0) | 41 (20.9) | 2.52** | – | 71.5 | 59.2 | 53.8 | 75.8 | 1.75 | 0.48 |
| Night + Insidious + Buttock (3/3) | 89 (68.5) | 81 (41.3) | 3.08** | – | 33.8 | 92.3 | 74.6 | 67.8 | 4.39 | 0.72 |
| Calin + Night (5/6) | 40 (30.8) | 11 (5.6) | 7.48** | – | 40.0 | 79.1 | 55.9 | 66.5 | 1.91 | 0.76 |
| Berlin + Insidious (3/5) | 93 (71.5) | 80 (40.8) | 3.65** | – | 68.5 | 58.7 | 52.4 | 73.7 | 1.66 | 0.54 |
| ASAS + Buttock (5/6) | 44 (33.8) | 15 (7.7) | 6.17** | – | 30.8 | 94.4 | 78.4 | 67.3 | 5.50 | 0.73 |
↵* p<0.05;
** p<0.001.