Fig. 1From: The establishment of a WHO Reference Reagent for anti-malaria (Plasmodium falciparum) human serumInter-laboratory variability is reduced when potency relative to the reference reagent 10/198 replaces direct measurement. Box histograms show ELISA derived values for 1/EC50 (left) and potency (right) for samples C1, C2, C3 and XC from each laboratory (1–16) with AMA-1 as the coating antigen (a), MSP-142 as the coating antigen (b), and MSP-3 (c)Back to article page