Calculated change in total IgG autoreactivity between visit 1 and visit 2 in Prog (progressor) and NProg (nonprogressor ) subgroups. Change was calculated for each autoantibody on the IgG array as visit 2 minus visit 1 values, and then these individual autoantibody change values were averaged for the whole array, yielding one overall result for each patient. Values > 0 correspond to increased IgG autoreactivity at visit 2. The two groups were compared using an unpaired Student's t-test.
Olsen et al. Arthritis Research & Therapy 2012 14:R174 doi:10.1186/ar3927