[Current aspects on evaluation of assays of factor-VIII activity, factor-VIII associated protein and factor-VIII neutralizing antibody (author's transl)].

In evaluating factor-VIII activity it should be noted that regarding the remaining activity of deficient plasma a linear reference curve is achieved. In the standard population factor-VIII activity and factor-VIII associated protein are distributed approximately lognormally. Due to this distribution certain results have been gained for the optimal choice of localisation and dispersion measures. It is assumed that the proportions of neutralized factor-VIII activity in plasma are distributed according to Poisson. The applicability of the Poisson distribution was also proved for the free factor-VIII activity portion. Due to the Poisson distribution the antibody unit is clearly defined, thus eliminating a further discussion on the establishment of an arbitrary standardized antibody unit.