DIN 58909-2:2000-03

The document is applicable to the determination of factor VIII coagulant activity (F VIII C) via the determination of factor Xa with a chromogenic peptide substrate in plasma and factor concentrates. The purpose of this document is to achieve comparable results for the factor VIII content in a given specimen. Essential preconditions for achieving this objective are a standardized procedure for calibration of the method, as well as the use of reference plasmas or reference concentrates with an assigned factor VIII C proportion which has been determined by calibration against the International Standard of WHO for factor VIII C which is valid at the time of use.