Laboratory reporting of the international normalized ratio: progress and problems.

Context: The international normalized ratio (INR) is widely used to monitor oral anticoagulation and to evaluate patients with coagulation disorders.

Objective: To examine the variability of the performance and reporting of the INR and to evaluate laboratory calculation of the INR.

Design: Between 1993 and 2003, laboratories participating in proficiency testing were surveyed.

Quality assurance in hemostasis: the perspective from the College of American Pathologists proficiency testing program.

External quality assurance (EQA) is an important component of the total quality assurance program of a clinical hemostasis laboratory. The College of American Pathologists (CAP) helps meet this requirement by providing a proficiency testing program that evaluates a broad range of hemostasis methods and analytes. This article reviews the published experience of the CAP proficiency testing program in hemostasis.

Effect of fondaparinux on coagulation assays: results of College of American Pathologists proficiency testing.

Context: Fondaparinux, a factor Xa inhibitor, is approved for thromboprophylaxis after orthopedic surgery and for treatment of venous thromboembolism. It may also be efficacious, safe, and cost-effective for other patients; thus, more widespread use of fondaparinux is likely. The effect of fondaparinux on coagulation testing needs to be thoroughly examined.

External peer review quality assurance testing in von Willebrand disease: the recent experience of the United States College of American Pathologists proficiency testing program.

The U.S. College of American Pathologists (CAP) has conducted a focused study of the proficiency testing for von Willebrand disease (vWD) analysis from 2003 to 2005.