Thrombin generation on 200 μmol/L PCPS at varying factor V (A), factor IX (B), protein C (C), and factors V, VIII, IX, and X simultaneously (D) concentrations. Thrombin generation was initiated by 5 pmol/L factor VIIa-TF in the presence of either factor V or factor IX, or protein C, or factors V, VIII, IX, and X simultaneously at 100% (▪), 150% (•), and 50% (▴) of their mean plasma concentrations. All other proteins were present at mean plasma concentrations.