Comparison of ETP and peak height measured in PRP samples in control subjects and FXI-deficient individuals. Discrimination between 41 control subjects and FXI-deficient patients divided into 3 groups: partial deficiency (FXI:C 16-60 IU/dL, n = 72), major deficiency 1 (Major 1) (FXI:C 3-15 IU/dL, n = 10), and major deficiency 2 (Major 2) (FXI:C ≤2 IU/dL, n = 8) using the TG assay triggered at TF 5 pM (A,C) and TF 0.5 pM (B,D). ETP (A-B) and peak height measurements (C-D) are compared in PRP samples with or without CTI. *P < .5, **P < .01, ***P < .001, ****P < .0001; ns, not significant.