Relation between the PSdAR and the pSR. Protein S–depleted plasma was mixed with increasing amounts of its corresponding parent plasma (0%, 20%, 40%, 60%, 80%, and 100% parent plasma) and coagulation was triggered with CaCl₂ (5 mM), factor Xa (20 pM), and phospholipids (6 μM DOPS/DOPC, 20/80 M/M) at indicated final concentrations. The PSdAR was plotted against the pSR.