174615.fig.004a
(a)
174615.fig.004b
(b)
Figure 4: Determination of variability in experiments conducted by 4 different analysts. Two samples were used (both final products of IFN-β 1a). The analysts who had no prior experiences of conducting the assay were instructed to conduct the experiments by following the protocol. Each sample was run in triplicate and tested on 3 different plates. The graphs represent the linear range of the tested doses as determined by comparison to the international reference standard.