Table 2

 Relative risk of developing rheumatoid factor (RF) positive rheumatoid arthritis, RF negative rheumatoid arthritis, and rheumatoid arthritis overall for subjects with different levels of formal education compared with a university degree, by sex

RF+ RARF− RATotal RA
Ca/CoRR95% CICa/CoRR95% CICa/CoRR95% CI
†Reference group.
Ca/Co, number of exposed cases/number of exposed controls; CI, confidence interval; RF, rheumatoid factor; RR, relative risk adjusted for age and residential area, or for age, residential area, and sex (category “All”).
Women
Compulsory school140/2121.61.1 to 2.460/2121.00.6 to 1.7200/2121.30.9 to 1.9
Vocational upper secondary school46/691.81.1 to 3.029/691.40.8 to 2.575/691.61.0 to 2.5
Theoretical upper secondary school49/941.60.9 to 2.625/940.90.5 to 1.674/941.20.8 to 1.8
Other education105/2091.30.9 to 1.956/2090.80.5 to 1.2161/2091.10.8 to 1.5
University degree†82/2041.061/2041.0143/2041.0
Men
Compulsory school62/952.11.1 to 4.128/951.70.7 to 4.190/952.01.1 to 3.5
Vocational upper secondary school33/651.50.7 to 3.218/652.00.7 to 5.351/651.70.9 to 3.3
Theoretical upper secondary school27/382.20.9 to 5.19/381.50.5 to 4.836/382.01.0 to 4.2
Other education40/622.11.1 to 4.025/624.01.5 to 10.565/622.51.4 to 4.5
University degree†22/751.012/751.034/751.0
All
Compulsory school202/3071.71.2 to 2.588/3071.20.8 to 1.8290/3071.51.1 to 2.0
Vocational upper secondary school79/1341.71.1 to 2.647/1341.50.9 to 2.5126/1341.61.1 to 2.3
Theoretical upper secondary school76/1321.71.1 to 2.634/1321.00.6 to 1.7110/1321.30.9 to 1.9
Other education145/2711.41.0 to 2.081/2711.10.7 to 1.6226/2711.31.0 to 1.7
University degree†104/2791.073/2791.0177/2791.0