|  | Patients with rheumatoid arthritis | Population controls |
---|---|---|---|
Mean age at diagnosis, years (range) a | 49 (18 to 65) | 48 (16 to 68) | |
Gender | Women | 366 (71.1%) | 478 (62.2%) |
 | Men | 149 (28.9%) | 291 (37.8%) |
Birth year | Before 1940 | 71 (13.8%) | 98 (12.7%) |
 | 1940 to 1949 | 171 (33.2%) | 250 (32.5%) |
 | 1950 to 1959 | 145 (28.2%) | 223 (29.0%) |
 | 1960 to 1969 | 77 (15.0%) | 129 (16.8%) |
 | 1970 or after | 51 (9.9%) | 69 (9.0%) |
Place of residence | Copenhagen | 86 (16.7%) | 102 (13.3%) |
 | Suburbs of Copenhagen | 90 (17.5%) | 137 (17.8%) |
 | Other towns with ≥100,000 inhabitants | 78 (15.2%) | 77 (10.0%) |
 | Towns with 10,000 to 99,999 inhabitants | 93 (18.1%) | 197 (25.6%) |
 | Rural areas/towns with <10,000 inhabitants | 168 (32.6%) | 256 (33.3%) |
Education b | No post-school education | 123 (23.9%) | 120 (15.6%) |
 | Semi-skilled worker, short education (<1 year) or apprentice | 204 (39.6%) | 293 (38.2%) |
 | Short or middle length advanced studies (1 to 4 years) | 156 (30.3%) | 265 (34.5%) |
 | Long advanced studies (>4 years) | 32 (6.2%) | 90 (11.7%) |