Assessment of the intraobserver and interobserver variability for the evaluation of synovial histopathology
| Variable | Intraobserver variability | Interobserver variability | ||||
|---|---|---|---|---|---|---|
| Complete concordance | ⩽1 Step difference | >1 Step difference | Complete concordance | ⩽1 Step difference | >1 Step difference | |
| (%) | (%) | (%) | (%) | (%) | (%) | |
| Twenty nine synovial samples with a large variability in degree and type of synovial inflammation were blindly scored for 12 different histopathological features on a semiquantitative scale from 0 to 3. The concordance was calculated between two independent scores by the same observer and independent scores by two different observers. | ||||||
| Lining layer thickness | 90 | 10 | 0 | 61 | 26 | 13 |
| Vascularity | 59 | 39 | 2 | 35 | 65 | 0 |
| Lymphoid aggregates | 88 | 12 | 0 | 78 | 21 | 1 |
| Inflammatory infiltration | 76 | 22 | 2 | 30 | 65 | 5 |
| Plasma cells | 76 | 17 | 7 | 48 | 44 | 8 |
| Polymorphonuclear cells | 64 | 34 | 2 | 52 | 35 | 13 |
| CD3+ T lymphocytes | 66 | 33 | 1 | 32 | 66 | 2 |
| CD20+ B lymphocytes | 81 | 15 | 4 | 67 | 28 | 5 |
| CD38+ plasma cells | 86 | 9 | 5 | 83 | 12 | 5 |
| CD1a+ dendritic cells | 85 | 15 | 0 | 67 | 29 | 4 |
| Intracellular citrullinated proteins | 100 | 0 | 0 | 95 | 5 | 0 |
| mAb12A staining | 92 | 8 | 0 | 73 | 27 | 0 |
| Mean of all markers | 80 | 18 | 2 | 60 | 35 | 5 |