Comparison of demographic, clinical, and serological data for the present series with similar data from other, non-European countries
| Present series | Steen, et al,24Arthritis Rheum, 1988 | Chandran, et al,25 Aust New Z J Med, 1995 | Kuwana, et al,26Arthritis Rheum, 1994 | |
| Number of patients | 290 | 397 | 1159-150 | 2759-151 |
| Women (%) | 84 | 83 | 84 | 86 |
| Limited/diffuse/overlap SSc | 1.5/1/0 | 0.9/1/0 | 6/1/1.6 | 7 : 5.7 : 3 |
| Mean age at onset | 53 | 42 | — | 41 |
| Raynaud's phenomenon (%) | 92 | 96 | — | 98 |
| Digital pitting (%) | 62 | 66 | — | 25 |
| Telangiectasia (%) | 67 | 82 | — | — |
| Calcinosis (%) | 26 | 39 | — | — |
| Joint involvement (%) | 66 | 64 | — | 33 |
| Scleroderma renal crisis (%) | 0 | — | 1 | — |