Basic demographic characteristics
| Seropositive sIBM Median (min, max) | Seronegative sIBM Median (min, max) | |
|---|---|---|
| Mean age | 67.0 (47.0, 77.0) | 70.0 (60.0, 85.0) |
| Mean age at onset | 55.5 (45.0, 71.0) | 54.0 (54.0, 78.0) |
| Duration of illness | 10.0 (3.0, 15.0) | 11.0 (4.0, 24.0) |
sIBM, sporadic inclusion body myositis.