In US: For Research Use Only. Not for Use in Diagnostic Procedures. Deficient plasma for the assay of Factor VIII:C. All the clotting factors are present (constant and in the normal range, brought by the deficient plasma), except for FVIII:C, which is brought by the diluted tested plasma, and clotting is triggered with cephalin, activator and calcium (APTT). FVIII:C is the limiting factor and clotting time is inversely proportional to the concentration of FVIII:C.
