Summary of field study data compared with average SynthASil OSA results. (A) R338L-FIX:C of field study samples measured by the SynthASil OSA plotted against the values in the same samples measured by 13 different OSAs and 2 CSAs against a hemophilia B (red) or normal (blue) background. (B) Comparison of FIX activity in plasma samples spiked with normal pdFIX-WT (SSC Lot 4, 105 IU/dL FIX:C) and rR338L-FIX (100 IU/dL nominal activity by SynthASil) across 13 OSAs and 2 CSAs. Symbols indicate the activating surface corresponding to each assay. Error bars indicate interlaboratory standard deviation; all linear regression fits, R2 >0.98. Mean differences between any 2 assays were compared separately for pdFIX-WT and rR338L-FIX using Tukey’s multiple comparison adjustment with an overall type I error rate of 0.05. Only comparisons to SynthASil are shown. ∗∗P < .01, and ∗∗∗∗P < .0001. ns, not significant.
