Fig. 2.

Bivariate scatterplots of the relationship between measurements by Meso Scale Discovery (MSD) and proximity extension assay (PEA) in synovial fluid (A) and serum (B). For each panel two graphs are shown: Above in red, log transformed cytokine concentration measured by MSD and PEA with a diagonal line of equality and the Pearson correlation coefficient (r). Below in blue, Bland-Altman plots of difference versus MSD measurement after log transformation with mean difference and 95% limits of agreements as thick horizontal lines, with a thin line at 0 indicating no difference. The statistical data for the correlation analyses are shown in Table S10. NPX ​= ​normalized protein expression. s ​= ​serum. sf ​= ​synovial fluid.