Figure 2

Proportion anticitrullinated peptide antibody-positive cases in pre–rheumatoid arthritis cases by years prior to rheumatoid arthritis diagnosis. Proportion of positive cases for any anticitrullinated peptide antibody (ACPA) and peptide-specific ACPAs in pre–rheumatoid arthritis (RA) cases with blood drawn 10 or more years (n = 61), 5 years to less than 10 years (n = 67) and less than 5 years before diagnosis (n = 64) in the Nurses’ Health Study and Nurses’ Health Study II. CI: confidence interval, RR: risk ratio.