*Maximum value of RF measured in the cohort project during 2000–2010 for each individual was used.†Cut-off = 4.5 IU/ml.IORRA, Institute of Rheumatology Rheumatoid Arthritis cohort study; BMI, body mas
The reported Rate Ratios describe the variations in costs expressed as a multiplicative factor for patients presenting the associated characteristic compared to those who did not, all other things bei
