U.K. NEQAS for Blood Coagulation
Main Scheme; Level 1 & Level 2
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.
Please contact UK NEQAS for Blood Coagulation email@example.com 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:
Prothrombin Time (PT)/INR (Quick / capillary methods)
Factor II assay
Von Willebrand factor antigen assay
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
Factor XII assay
Protein S total and free antigen assay
Factor XIII screen/assay*
Protein S activity assay
Quantitative VIII inhibitor*
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 above 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. Survey newsletters provide additional information. 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 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.
Repeat samples may be requested (subject to availability) by participants during a survey if problems are encountered when performing the test/assay, and after a survey is closed to investigate performance issues. Participants are requested to retain their survey instruction sheets for information on how to process the samples.