U.K. NEQAS for Blood Coagulation Main Scheme; Level 1 & Level 2 INTRODUCTION By providing external quality assessment for blood coagulation tests, as a part of overall quality assurance, the programme aims to promote high standards of performance and practice, achieved with the UK NEQAS primary aim of education, by provision of independent, objective and impartial information. WHO CAN TAKE PART? Although primarily intended to meet the needs of clinical laboratories, participation by industrial and other laboratories is welcomed. Most participating laboratories are sited within the UK, but registration is open to laboratories in Europe and further afield, whether government supported, private or commercial. UK NEQAS for Blood Coagulation is run on a not for profit basis, under the auspices of UK National External Quality Assessment Service and professional bodies. REGISTRATION Please contact UK NEQAS for Blood Coagulation neqas@coageqa.org.uk to request a registration form for the programme The nominated participant, normally the person with overall responsibility for the laboratory, registers for all tests included in UK NEQAS for Blood Coagulation, which their laboratory offers as a service. As part of registration, participants are requested to formally agree to adhere to the Joint Working Group’s Conditions of Participation in UK EQA Schemes. With the few exceptions indicated in these Conditions, the Director is obliged to observe strict confidentiality regarding individual performance. HOW DOES IT WORK? The tests are divided into Level 1 (screening tests) and Level 2 (assays), comprising: Level 1 | Level 2 | Prothrombin Time (PT)/INR (Quick / capillary methods) | Factor II assay | Von Willebrand factor antigen assay | PT (diagnostic) | Factor V assay | VWF:RCo (activity) assay | Activated Partial Thromboplastin Time (APTT) | Factor VII assay | VWF:CB (collagen-binding) assay | Heparin Dosage Assessment (HDA) | Factor VIII:C assay | Antithrombin antigen assay | Heparin Assay (HA) | Factor IX:C assay | Antithrombin activity assay | Thrombin Time (TT) | Factor X assay | Protein C antigen assay | Fibrinogen evaluation (Clauss method) | Factor XI assay | Protein C activity assay | D-Dimer | Factor XII assay | Protein S total and free antigen assay | Lupus anticoagulant* | Factor XIII screen/assay* | Protein S activity assay | | Quantitative VIII inhibitor* | Plasminogen assay | | | Activated Protein C resistance assay |
Six exercises are distributed each financial year, and the range of tests included within these surveys varies; each exercise includes samples for PT/INR and APTT, and 4 surveys include samples for FVIII assay. Four surveys each year include samples for thrombophilia screening (Protein C, Protein S, Antithrombin, Activated Protein C resistance). Details of tests to be included in each survey are indicated in individual reports three months prior to survey distribution. All samples are of lyophilised plasma, from donors screened for hepatitis B surface antigen (HBsAg) and for antibodies to hepatitis C virus and human immunodeficiency virus types 1 and 2 (anti HIV-1+2). In the majority of cases, samples are from single donations. In addition to six main scheme distributions, relevant supplementary exercises (including those tests marked with an asterisk (*) in the avobe table) are distributed on an ad-hoc basis to address current issues in haemostasis. ANALYSIS OF RESULTS Individual reports for each survey are available within two weeks after the closing date for the survey. These may be downloaded from the online data entry system; and posted for centres wishing to retain paper copies. Additionally, some weeks after the individual results, an overall exercise report is made available to registered participants for electronic download from this website. This report includes comprehensive analysis of test results by methodology, together with graphically presented data analysis for each test specimen. PERFORMANCE ANALYSIS Performance is determined by comparison of individual laboratory results with the target value for each test. Full details of how this is determined may be found in the ‘Performance’ menu of this website. |