title: Quality assurance in hemostasis: the perspective from the College of American Pathologists proficiency testing program.
abstract: 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. The purpose is to formulate general conclusions about the benefits of EQA. Between 1963 and 2006, the performance characteristics of a variety of tests have been evaluated, including the prothrombin time, activated partial thromboplastin time, coagulation factor activity assays (e.g., fibrinogen, factor [F] VIII, FIX, FXI), von Willebrand factor assays, unfractionated heparin monitoring, lupus anticoagulant testing, and platelet function. Based on the results of these evaluations, the major benefits of EQA are to (1) enhance patient care and safety through improved laboratory testing; (2) characterize test accuracy and precision across multiple methods; (3) correlate specific method variables with accuracy and precision; (4) identify interfering substances and quantify their effects across multiple methods; (5) identify clinical laboratories that are at risk for poor performance so that their performance can improve; and (6) satisfy accreditation and regulatory requirements.
authors.affiliation: Department of Pathology, University of Kansas Medical Center, Kansas City, Kansas 66160, USA. mcunningham@kumc.edu
authors.forename: Mark T
authors.initials: MT
authors.lastname: Cunningham
authors.forename: John T
authors.initials: JT
authors.lastname: Brandt
authors.forename: Wayne L
authors.initials: WL
authors.lastname: Chandler
authors.forename: Charles S
authors.initials: CS
authors.lastname: Eby
authors.forename: Timothy E
authors.initials: TE
authors.lastname: Hayes
authors.forename: Jayashree
authors.initials: J
authors.lastname: Krishnan
authors.forename: Jerry B
authors.initials: JB
authors.lastname: Lefkowitz
authors.forename: John D
authors.initials: JD
authors.lastname: Olson
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: Stasik
authors.forename: Jun
authors.initials: J
authors.lastname: Teruya
authors.forename: Elizabeth M
authors.initials: EM
authors.lastname: Van Cott
mesh_terms: D001780:Blood Coagulation Tests; D001792:Blood Platelets / Q000378:metabolism*; D002624:Chemistry, Clinical / Q000379:methods; D019411:Clinical Laboratory Techniques; D005164:Factor IX / Q000096:biosynthesis; D005169:Factor VIII / Q000096:biosynthesis; D005172:Factor XI / Q000096:biosynthesis; D005340:Fibrinogen / Q000096:biosynthesis; D006487:Hemostasis; D006493:Heparin / Q000096:biosynthesis; D006801:Humans; D010336:Pathology / Q000379:methods* / Q000592:standards*; D011786:Quality Control; D014481:United States; D014841:von Willebrand Factor / Q000096:biosynthesis
chemical_list: D014841:von Willebrand Factor; D005169:Factor VIII; D005164:Factor IX; D005340:Fibrinogen; D006493:Heparin; D005172:Factor XI