Additional file 8 of Presence of autoantibodies in 'seronegative' rheumatoid arthritis associates with classical risk factors and high disease activity

Additional file 8: Supplementary Table 7. Associations between RF isotypes and smoking, in anti-CCP2-positive and anti-CCP2-negative RA. Odds ratios with 95% confidence intervals are shown for associations between smoking and presence/absence of IgM, IgG or IgA RF, in anti-CCP2-positive and -negative RA; p-values indicate differences in ORs between RF isotype-positive and -negative subsets.