Sociodemographic and clinical characteristics
| Overall (N=2090) | Male (N=1212, 58%) | Female (N=878, 42%) | |
| Age | |||
| Mean (SD) | 45.2 (11.2) | 44.4 (10.4) | 46.3 (12.2) |
| 18–44 years | 1141 (55%) | 689 (57%) | 452 (51%) |
| 45–64 years | 802 (38%) | 459 (38%) | 343 (39%) |
| 65–74 years | 120 (6%) | 49 (4%) | 71 (8%) |
| 75+ years | 27 (1%) | 15 (1%) | 12 (1%) |
| Are there other people in your family who also have rheumatoid arthritis? | |||
| Yes | 501 (24%) | 310 (26%) | 191 (22%) |
| No | 1524 (73%) | 871 (72%) | 653 (74%) |
| Unsure | 65 (3%) | 31 (3%) | 34 (4%) |
| Have had children | |||
| No | 262 (13%) | 145 (12%) | 117 (13%) |
| Yes | 1828 (87%) | 1067 (78%) | 761 (77%) |
| Have you had children after being diagnosed with rheumatoid arthritis? | |||
| Yes | 364 (20%) | 261 (24%) | 103 (14%) |
| No | 1448 (79%) | 799 (75%) | 649 (85%) |
| Unsure | 16 (1%) | 7 (1%) | 9 (1%) |
| Not applicable | 262 (13%) | 145 (12%) | 117 (13%) |
| Planning to have children in the future | |||
| Yes | 488 (23%) | 352 (29%) | 136 (15%) |
| No | 1602 (77%) | 860 (71%) | 742 (85%) |
| Racial background (USA or UK) | |||
| White | 321 (98%) | 159 (99%) | 162 (97%) |
| Black/African/Caribbean | 4 (1%) | 1 (1%) | 3 (2%) |
| Asian/Asian British | 1 (0%) | 0 (0%) | 1 (1%) |
| Other | 1 (0%) | 0 (0%) | 1 (1%) |
| Prefer not to say | 1 (0%) | 1 (1%) | 0 (0%) |
| Not applicable | 1762 (84%) | 1051 (87%) | 711 (81%) |
| Education | |||
| Elementary school | 45 (2%) | 37 (3%) | 8 (1%) |
| High school | 541 (26%) | 278 (23%) | 263 (30%) |
| Some college/university | 272 (13%) | 114 (9%) | 158 (18%) |
| College/university degree | 1017 (49%) | 612 (50%) | 405 (46%) |
| Postgraduate degree | 88 (4%) | 73 (6%) | 15 (2%) |
| Other | 6 (0%) | 3 (0%) | 3 (0%) |
| Employment status | |||
| Employed, full time | 1432 (69%) | 918 (76%) | 514 (59%) |
| Employed, part time | 240 (11%) | 120 (10%) | 120 (14%) |
| Self-employed | 65 (3%) | 45 (4%) | 20 (2%) |
| Voluntary work | 14 (1%) | 8 (1%) | 6 (1%) |
| Homemaker | 35 (2%) | 5 (0%) | 30 (3%) |
| Student | 11 (1%) | 6 (0%) | 5 (1%) |
| Unemployed | 37 (2%) | 14 (1%) | 23 (3%) |
| Retired | 182 (9%) | 81 (7%) | 101 (12%) |
| On sick leave | 23 (1%) | 4 (0%) | 19 (2%) |
| Maternity/paternity leave | 2 (0%) | 1 (0%) | 1 (0%) |
| Not able to work due to disability | 49 (2%) | 10 (1%) | 39 (4%) |
| Insurance status | |||
| Private insurance | 1026 (49%) | 636 (52%) | 390 (44%) |
| National health insurance | 1409 (67%) | 794 (66%) | 615 (70%) |
| Veterans Affairs | 17 (1%) | 10 (5%) | 7 (4%) |
| Medicare | 178 (9%) | 92 (48%) | 86 (50%) |
| Medicaid | 42 (2%) | 27 (14%) | 15 (9%) |
| None | 3 (0%) | 2 (1%) | 1 (1%) |