 Whole blood specimens will be drawn as described above. Measurements will be performed on two roTEG Coagulation Analyzers from Pentapharm. RoTEG all-plastic reaction cups are procured from the manufacturer. Polypropylene and polyethylene pipettes are used to handle reagents and blood. Citrated whole blood will be re-calcified by 20 mcl 0.2 molL CaCl2 and activated by 20 mcl solution of recombinant human TF Innovin diluted 1:1000 using a sodium barbital buffer. The measured parameters have been defined by the manufacturer as follows: The clotting timeCT is the time in seconds from Ca2 activation of coagulation and until an increase in elasticity corresponding to 2 graphical mm is obtained on the ordinate. The clot formation time CFT is the time in seconds passing while the elasticity increases from 2 mm to 20 mm on the ordinate. The maximum clot formation MCF expresses the maximum strength in millimeters of the final clot. Several additional parameters representing the continuous registration of clot formation have been defined by Sorensen et al 28: the maximum velocity MaxVel of clot formation, the time to maximum velocity T,MaxVel of clot formation, and the area under the velocity curve AUC. 