Monitoring clot formation in normal pooled human reference plasma with the kinetic microplate FV 1-stage coagulation assay. Fibrin clot formation in NHP was monitored at 405nm over time in a microplate reader. The profile represents the actual microplate reader output of a 6 minute reaction of 32-fold diluted NHP, FV-deficient plasma, thromboplastin, and calcium chloride in a single microplate well. The vertical axis denotes the change in absorbance at 405nm that occurred as a result of clot formation in plasma. The time of fibrin formation was defined as the time to reach the half maximal increase in absorbance; approximately the midpoint of curve (36.40 seconds). The initial rate of clot formation was defined as the rate of change of absorbance at 405nm over the first 5 time points of the linear increase of absorbance portion of the curve (611.88 mUnits/min). The extent of clot formation was defined as the difference between the maximum and minimum absorbance at 405nm (0.35 Units).