C4A and systemic lupus erythematosus: Considering the above-mentioned parameter pairs, R2 adjusted was low (anti-dsDNA concentration, as measured by ELiA dsDNA, and complement C4 concentrations with SLE and control patients considered together: coefficient estimate=-0.0006, 95%-CI=-0.0012 - -0.0000, p=0.0454, R2 adjusted=0.037; anti-dsDNA concentration, as measured by anti-dsDNA-NcX ELISA; CRP concentrations with SLE and control patients considered together: coefficient estimate=0.0022, 95%-CI=0.0001 - 0.0043, p=0.0381, R2 adjusted=0.036).