Table 5.

Kappa (SE) between the different methods using different cut-offs.

Cut-off	3 μg/ml	4 μg/ml	5 μg/ml	6 μg/ml	7 μg/ml	8 μg/ml	9 μg/ml	10 μg/ml
In-house
Sanquin	0.774 (0.046)	0.748 (0.049)	0.6961 (0.054)	0.660 (0.058)	0.636 (0.060)	0.6161 (0.063)	0.582 (0.066)	0.615 (0.065)
QB	0.891 (0.034)	0.806 (0.043)	0.738 (0.050)	0.696 (0.053)	0.655 (0.057)	0.630 (0.060)	0.624 (0.062)	0.601 (0.064)
R-Biopharm	0.835 (0.041)	0.732 (0.049)	0.753 (0.047)	0.687 (0.051)	0.699 (0.053)	0.636 (0.057)	0.629 (0.058)	0.660 (0.058)
Sanquin
QB	0.753 (0.047)	0.711 (0.050)	0.711 (0.059)	0.774 (0.047)	0.815 (0.044)	0.8198 (0.044)	0.823 (0.045)	0.817 (0.047)
R-Biopharm	0.744 (0.047)	0.684 (0.050)	0.684 (0.050)	0.676 (0.052)	0.691 (0.052)	0.702 (0.052)	0.721 (0.051)	0.742 (0.052)
QB
R-Biopharm	0.901 (0.032)	0.902 (0.032)	0.860 (0.037)	0.849 (0.038)	0.847 (0.039)	0.832 (0.041)	0.771 (0.048)	0.747 (0.051)

QB, Quantum Blue^® Infliximab: Quantitative Lateral Flow Assay (Bühlmann, Schönenbuch, Switzerland); SE, standard error.