External quality assessment schemes in coagulation in Germany: between regulatory bodies and patient outcome.

In the early 1980s, the first external quality assessment schemes (EQAS) regarding parameters of the coagulation laboratory were established in the daily routine of German laboratories. At present, the EQAS performed by INSTAND offers a wide range of global and single parameters of thrombosis and hemostasis. Only the participation in prothrombin time and activated partial thromboplastin time exercises is mandatory. However, devices applied for patient self-management of oral anticoagulation are not included. This article provides an overview of the EQA activities of INSTAND regarding different coagulation parameters. Problems in acquiring adequate sample material and strategies in establishing acceptability ranges are also discussed.