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Background: Vaccine-induced immune thrombocytopenia and thrombosis (VITT) following the administration of the AstraZeneca (AZ) ChAdOx1 nCOV-19 vaccine is a well recognized clinical phenomenon. The associated clinical and laboratory features have included thrombosis at unusual sites, thrombocytopenia, raised D-dimer levels and positivity for immunoglobulin G (IgG) anti-platelet factor 4 (PF4) antibodies. Objectives: A collaborative external quality assessment (EQA) exercise was carried out by distributing five lyophilized samples from subjects with VITT and one from a healthy subject to 500 centers performing heparin-induced thrombocytopenia (HIT) testing. Methods: Participating centers employed their locally validated testing methods for HIT assays, with some participants additionally reporting results for VITT modified assays. Results: A total of 385 centers returned results for anti-PF4 immunoassay and functional assays. The ELISA assays used in the detection of anti-PF4 antibodies for the samples distributed had superior sensitivities compared with both the functional assays and the non-ELISA methods. Conclusion: ELISA-based methods to detect anti PF4 antibodies have a greater sensitivity in confirmation of VITT compared with functional assays regardless of whether such functional assays were modified to be specific for VITT. Rapid immunoassays should not be employed to detect VITT antibodies.

There may be clinically relevant differences between results of different FIX assays in samples containing extended half life FIX concentrates requiring regular surveillance of assay results through proficiency testing exercises. Control materials used in proficiency testing must be commutable, that is have the same inter-assay properties as those demonstrated by authentic clinical samples when measured by different analytical methods.We assessed relationships between results with different FIX assays and commutability of UK National External Quality Assessment Scheme (NEQAS) materials containing rIX-FP (Idelvion) or rFIXFc (Alprolix) by comparing results obtained using widely used one-stage and chromogenic assays during a proficiency testing exercise with results obtained when analysing a series of individual patient samples using the same assay systems. NEQAS samples prepared by addition of either Idelvion or Alprolix to FIX deficient plasma were sent to 76 haemophilia centres in Europe. A total of 18 Idelvion and 22 Alprolix patient samples were assayed in a single centre. Two chromogenic and two one-stage assays were compared.The pattern of results obtained for NEQAS samples and patient samples was similar. In all cases, the NEQAS sample data point was within the scatter of patient sample data in plots of patient sample results showing one-stage assay results using Synthasil or Actin FS plotted against chromogenic assay results with Biophen or Rox chromogenic FIX kits.This indicates that the NEQAS samples containing Idelvion or Alprolix were commutable and therefore suitable for use in proficiency testing exercises.

Background Vaccine-induced immune thrombocytopenia and thrombosis (VITT) following the administration of the AstraZeneca (AZ) ChAdOx1 nCOV-19 vaccine has recently been reported. The associated clinical and laboratory features have included thrombosis at unusual sites, thrombocytopenia, and raised D-dimers with positivity for IgG anti-platelet factor 4 (PF4) antibodies. Objectives A UK National External Quality Control Assessment Scheme external quality control exercise was carried out by distributing liquid and lyophilized samples from a subject with VITT, a pool of samples from subjects with classical heparin-induced thrombocytopenia (HIT), and a non-VITT/non-HIT case to 85 centers performing HIT testing. Methods Participating centers employed their locally validated testing methods for HIT assays. Results The lyophilized and liquid samples were found to be commutable for the ELISA assays used in the detection of anti-PF4 antibodies. The Aeskulisa, Stago, Hyphen, and LIFECODES anti-PF4 ELISA assays successfully detected the VITT antibody, whereas the Acustar HIT, Werfen LIA, and the Stago STIC assays did not. Conclusion It is important that clinical and laboratory teams are aware of the limitations of some anti-PF4 assays when using them to aid diagnosis of VITT syndrome.

Von Willebrand disease (VWD) is one of the most common hereditary bleeding disorders. Effective management of patients and their families depends on accurate diagnosis and subtype classification, and quality assurance including participation in proficiency testing programs is essential to ensure the accuracy of the panel of assays required to achieve this diagnosis. We report here findings from recent external quality assessment (EQA) exercises, as well as from a questionnaire about diagnostic practices employed by centers in the United Kingdom National Quality Assessment Scheme (UK NEQAS) performing von Willebrand factor (VWF) assays. Plasma samples from donors with VWD, “normal” donors, the International Society for Thrombosis and Haemostasis Scientific Subcommittee (ISTH SSC) plasma standard, and whole blood samples were sent to participants in the UK NEQAS BC program for VWF investigation. Calibration of lot#5 of the ISTH SSC plasma standard was shown to give improved comparability between the recovered value from an EQA exercise and the assigned potency for VWF activity assays. Diagnostic accuracy and precision amongst UK NEQAS participants was good, with an average 99% of centers reporting the correct interpretation for normal, type 1 and type 2 VWD samples, 100% diagnostic accuracy for centers performing FVIII binding assays, and good agreement amongst centers performing multimeric analysis. Genetic analysis of the VWF gene by specialist centers demonstrated errors in the genotyping process in one center, but also demonstrated failings in the interpretation of results in other centers. Despite evidence of good laboratory accuracy and precision in their assays, a questionnaire identified marked variation in diagnostic criteria employed, underlining the importance of guidelines to support the diagnosis of VWD.

Background Patients with hemophilia B are increasingly treated with extended half‐life (EHL) factor IX (FIX) concentrates. For the laboratory, introduction of these EHL concentrates presents a major challenge. To understand the variation in FIX activity levels, all available diagnostic assays need to be directly compared. Methods The ECAT, UKNEQAS, and RCPAQAP have collaboratively performed a global survey to evaluate the quality of FIX measurements using FIX deficient plasma samples spiked with recombinant FIX (rFIX), rFIXFP, rFIXFc, and N9‐GP to levels at typical FIX trough (6 IU/dL) and peak levels (60 IU/dL). Participants were asked to use their routine protocols, using one‐stage assays (OSA) or chromogenic assays (CA). Results In samples spiked with 6 IU/dL product, median (25%‐75% range) FIX activity levels (OSA), were 8.0 IU/dL (7.0‐9.2) for rFIX, 6.0 IU/dL (4.0‐7.1) for rFIXFP, 6.6 IU/dL (5.5‐8.0) for rFIXFc, and 4.9 IU/dL (3.5‐8.4) for N9‐GP. In samples spiked with 60 IU/dL, FIX activity levels measured (using OSA) was 63.0 IU/dL (59.9‐67.0) for rFIX, 42.5 IU/dL (28.2‐47.0) for rFIXFP, 50.0 IU/dL (45.0‐55.0) for rFIXFc, and 34.0 IU/dL (24.8‐67.5) for N9‐GP. Considerable differences were observed between reagents for all samples. With CA, there was also quite some variation, but no differences between reagents. Conclusion Large variation is observed in the measurement of FIX activity levels after administration of rFIX and EHL FIX products. For N9‐GP, most silica‐based assays show especially high levels. It is essential to standardize and improve reliability of measurements of these concentrates as diagnosis and treatment monitoring is based on these results.

Introduction Inhibitor formation is the greatest challenge facing persons with haemophilia treated with factor concentrates. The gold standard testing methodologies are the Nijmegen-Bethesda assay (NBA) for FVIII and Bethesda assay (BA) for FIX inhibitors, which are affected by pre-analytical and inter-laboratory variability. Aims To evaluate inhibitor testing methodology and assess correlation between self-reported and actual methodology. Methods Methodology was evaluated using a survey distributed alongside a UK National External Quality Assessment Service Blood Coagulation external quality assurance (EQA) exercise for FVIII and FIX inhibitor testing. Results Seventy four survey and EQA exercise responses were received (response rate 63.2%), with 50 paired survey/EQA results. 47.1% (33/70) reported using the NBA and 42.9% (30/70) the BA for FVIII inhibitor testing. Review of FVIII inhibitor assay methodology demonstrated discrepancy (self-reported to actual) in 64.3% (BA reporting) and 27.6% (NBA reporting). Pre-analytical heat treatment was used by 32.4%, most commonly 56°C for 30 minutes. Assay cut-offs of 0.1-1.0 BU/mL were reported. EQA samples (acquired FVIII and congenital FIX) demonstrated titres and coefficients of variation (CV) of 3.1 BU/mL (0.7-15.4 BU/mL; CV = 43%) and 18.0 BU/mL (0-117 BU/mL; CV = 33%), respectively. No significant assay or laboratory factors were found to explain this variance, which could have resulted in change in management for 6 patients (5 misclassified high-titre FVIII inhibitors and 1 false negative for a FIX inhibitor). Conclusions Heterogeneity was seen at each stage of assay methodology. No assay-related factors were found to explain variation in inhibitor titres. Further standardization is required to improve inhibitor quantification to guide patient care.

External Quality Assessment (EQA) is an important part of laboratory quality assurance. Spiking of normal plasma is sometimes employed to mimic clinical samples. It is important that spiked material gives similar results to clinical samples (ie, is commutable) to ensure appropriate conclusions can be drawn from EQA exercises. We describe here data from UK National External Quality Assessment Scheme for Blood Coagulation (NEQAS BC) exercises where spiked samples were tested alongside samples from patients to explore commutability of artificial material. Normal plasma was spiked with unfractionated heparin (UFH), low molecular weight heparin (LMWH), Dabigatran or Rivaroxaban. Factor VIII (FVIII) deficient plasma was spiked with FVIII concentrate. Spiked samples and ex vivo patient material were sent to laboratories for testing. For LMWH, good agreement was seen between results for samples from patient plasma and plasma spiked with heparin. For UFH, APTT ratios differed between spiked and patient samples for the same drug concentration, with no correlation in ranking of reagents. Precision for patient and spiked material for Rivaroxaban and Dabigatran assays was comparable. However, the pattern of results for some Dabigatran assay kits differed between spiked and patient samples. For FVIII assays, results obtained with spiked and postinfusion samples gave comparable results. Spiked material is suitable for EQA if commutability is demonstrated. Our data show commutability for plasma spiked with Rivaroxaban, LWMH and some FVIII concentrates. For some tests, notably APTT for UFH, marked differences between patient and spiked samples indicate not all tests can be evaluated using artificial samples.

INTRODUCTION Mutations in fibrinogen (Fgn) genes, causing dysfibrinogenaemia, can result in either a bleeding or thrombophilic diathesis. Dysfibrinogenaemia is infrequently encountered in hospital laboratories, and the utility of different assays in the diagnosis of dysfibrinogenaemia has not previously been explored in a multicentre study. We describe here an exercise in which PRO-RBDD project (prospective data collection on patients with fibrinogen and Factor XIII deficiencies) centres, and UK NEQAS centres, performed investigations for dysfibrinogenaemia. METHODS Samples from donors with dysfibrinogenaemia (sample 1: gamma p.Arg301Cys, sample 2: Bbeta166Arg3Cys-Fgn Longmont, sample 3: Aalpha p.Arg35His) and a normal donor were sent to laboratories for investigation for possible dysfibrinogenaemia. Median, coefficient of variation and range were determined for each assay method. RESULTS Results were returned from 62 UK NEQAS and 24 PRO-RBDD centres. PT, APTT, Clauss fibrinogen and thrombin times were performed by >90% of centres, with 51% performing reptilase times, and 31% fibrinogen antigen. All centres identified samples 1 and 3 as abnormal. However, 39% of centres reported a normal or raised fibrinogen for the Fgn Longmont sample, and marked differences in Clauss fibrinogen results with different reagents were noted for this sample (median 1.01 g/L vs 5.10 g/L for the two mostly widely used reagents). CONCLUSION In-house studies suggest that the method of detection of fibrin clot formation may result in different Clauss fibrinogen measurements with FgnLongmont plasma. It is possible that some widely used methodologies, both using optical and mechanical end-point detection systems, will fail to detect this rare fibrinogen variant.

INTRODUCTION FXIII deficiency is a rare bleeding disorders, and specific FXIII assays are recommended to detect this deficiency. We investigated the performance and accuracy of FXIII investigations in two exercises, comparing centres enrolled in the PRO-RBDD project (prospective data collection on patients with fibrinogen and Factor XIII deficiencies), and UK NEQAS BC centres. METHODS Samples from a FXIII deficient subject and a normal donor were sent to participating centres, to investigate for FXIII deficiency, and interpret their results. Median, coefficient of variation and range were determined. RESULTS Results were returned from 98 UK NEQAS BC and 28 PRO-RBDD centres. Up to 40% of UK NEQAS BC and 52% of PRO-RBDD centres reported clot solubility results - with diagnostic errors by two NEQAS BC centres (false negatives for the FXIII deficient sample) and one PRO-RBDD centre (false positive for the normal sample). Over 70% of UK NEQAS BC centres and PRO-RBDD centres performed FXIII assays. Median results were similar between the two groups, with the exception of sample 3 in survey 2 (5.5 vs. 14.0 μ/dl for UK NEQAS BC and PRO-RBDD centres respectively, P < 0.001). Diagnostic errors were made by 2 UK NEQAS BC centres. CONCLUSION Approximately 70% of centres now employ FXIII assays, complying with international recommendations. However, solubility tests continue to be used. Our data show this can be successful, depending on the sensitivity of the method in use. Diagnostic errors are made by centres using both solubility screens and FXIII assays, and laboratories should ensure good quality assurance procedures to improve diagnostic accuracy.

INTRODUCTION: Variability in FVIII measurement is a recognized problem. There are limited data for samples containing recombinant Factor VIII Fc fusion protein (rFVIIIFc). Many studies use samples for which factor concentrate has been spiked into FVIII deficient plasma in vitro. This approach requires validation. AIM/METHODS: Four samples were distributed in a UK National External Quality Assessment Scheme for Blood Coagulation (NEQAS BC) survey. One contained Advate (full-length recombinant FVIII) (rFVIII) added to FVIII deficient plasma, one was from a severe haemophilia A patient after infusion of Advate, one was prepared by addition of rFVIIIFc (marketed as Elocta/Eloctate) to FVIII deficient plasma and the fourth was collected from a severe haemophilia A patient following rFVIIIFc (Eloctate) infusion. Fifty-three haemophilia centres (UK and Scandinavia) performed one-stage FVIII assays and 27 performed chromogenic FVIII assays. RESULTS/CONCLUSIONS: One-stage assays gave significantly lower results than chromogenic assays by 7% (P

Accepting that standardizing and harmonizing laboratory practice has considerable value within laboratory medicine, including within the field of hemostasis, this paper concentrates on some recent and important initiatives in harmonizing hemostasis practice. Harmonization of hemostasis practice to improve clinical diagnosis and management is best driven by evidence and, in the absence of evidence, by consensus and expert opinion. To such end, there are various groups involved in such initiatives, and recent initiatives by these groups are highlighted in this review.

Introduction von Willebrand disease (VWD), the most common inherited bleeding disorder, is due to deficiencies/defects in von Willebrand factor (VWF). Effective diagnosis requires testing for FVIII, VWF antigen and one or more VWF ‘activity’ assays. Classically, ‘activity’ is assessed using ristocetin cofactor (VWF:RCo), but collagen binding (VWF:CB) and/or other assays are used by many laboratories. This extensive international cross-laboratory study has specifically evaluated contemporary VWF activity assays for comparative sensitivity to reduction in high molecular weight (HMW) VWF, and their ability to differentiate type 1 vs 2A VWD-like samples. Materials and methods A set of four samples representing step wise reduction in HMW VWF were tested by over 400 laboratories worldwide using various assays. A second set of two samples representing type 1 or type 2A VWD-like plasma was tested by a subset of 251 laboratories. Results Combined data identified some differences between VWF activity assays, with sensitivity for reduction of HMW being highest for VWF:CB and VWF:GPIbM, intermediate for VWF:RCo and VWF:GPIbR, and lowest for VWF:Ab. ‘Within’ method analysis identified the Stago method as the most sensitive VWF:CB assay. A large variation in inter-laboratory CV (e.g., 7–24% for the normal sample) was also demonstrated for various methods. Although performance of various methods differed significantly, most laboratories correctly differentiated between type 1 and 2 samples, irrespective of VWF activity assay employed. Conclusions These results hold significant clinical implications for diagnosis and therapy monitoring of VWD, as well as potential future diagnosis and therapy monitoring of thrombotic thrombocytopenic purpura (TTP).

Laboratory quality programs rely on internal quality control and external quality assessment (EQA). EQA programs provide unknown specimens for the laboratory to test. The laboratory's result is compared with other (peer) laboratories performing the same test. EQA programs assign target values using a variety of methods statistical tools and performance assessment of 'pass' or 'fail' is made. EQA provider members of the international organization, external quality assurance in thrombosis and hemostasis, took part in a study to compare outcome of performance analysis using the same data set of laboratory results. Eleven EQA organizations using eight different analytical approaches participated. Data for a normal and prolonged activated partial thromboplastin time (aPTT) and a normal and reduced factor VIII (FVIII) from 218 laboratories were sent to the EQA providers who analyzed the data set using their method of evaluation for aPTT and FVIII, determining the performance for each laboratory record in the data set. Providers also summarized their statistical approach to assignment of target values and laboratory performance. Each laboratory record in the data set was graded pass/fail by all EQA providers for each of the four analytes. There was a lack of agreement of pass/fail grading among EQA programs. Discordance in the grading was 17.9 and 11% of normal and prolonged aPTT results, respectively, and 20.2 and 17.4% of normal and reduced FVIII results, respectively. All EQA programs in this study employed statistical methods compliant with the International Standardization Organization (ISO), ISO 13528, yet the evaluation of laboratory results for all four analytes showed remarkable grading discordance.

Molecular genetic analysis of families with hemophilia and other heritable bleeding disorders is a frequently requested laboratory investigation. In the United Kingdom, laboratories undertaking genetic testing must participate in a recognized external quality assessment scheme for formal accreditation. The UK National External Quality Assessment Scheme (UK NEQAS) for heritable bleeding disorders was established in its current format in 2003, and currently has 27 registered participants in the United Kingdom, the European Union (EU), and the non-EU countries. Two exercises per annum are circulated to participants comprising either whole blood or DNA isolated from cell lines, and laboratories are allowed 6 weeks to analyze the samples and generate a report. Reports are assessed by a panel comprising clinicians and scientists with expertise in this area. Samples to date have involved analysis of the F8 gene (10 exercises), the F9 gene (4 exercises), and the VWF gene (3 exercises) and have comprised a wide spectrum of mutations representing the routine workload encountered in the molecular genetics laboratory. The majority of laboratories in each exercise passed, but a small number did not and reasons for failing included clerical errors, genotyping inaccuracies, and a failure to correctly interpret data. Overall we have seen an improvement in quality of reports submitted for assessment, with a more concise format that will be of value to referring clinicians and counsellors. Informal feedback from participants has been very positive.

In 2005, several external quality assurance (EQA) providers met and formed the External Quality Assurance in Thrombosis and Hemostasis (EQATH) group, although a formal Charter was not enacted until 2016. The goals of EQATH are to: identify the organizations involved with EQA in thrombosis and hemostasis; determine the functions and scope of these EQA programs; share information with the goal of improving the quality of existing programs and to seek methods that may standardize some activities; develop EQA samples that can be shared among EQA programs to determine the variation that may exist is various regions of the world; inform laboratories participating in EQA programs of the identified problems in laboratory testing; work with existing ISTH Scientific Subcommittees and Working Groups, providing information regarding clinical laboratory needs for standards and to help with the validation and value setting of standards; work with other organizations in developing recommendations and guidelines for EQA program activities; collaborate with other organizations and societies with interests in the quality of diagnostic coagulation testing. Since its beginning, the EQATH group has met regularly, completed two international projects, collaborated in the completion of four others and developed a guidance document for developing an EQA program in thrombosis and hemostasis. The group is now engaged in two additional projects that are underway.

The Library Management Group of The University Of Huddersfield set up a pilot study to examine altemative procedures for classifying and cataloguing library material in the Health sciences. The study tested the impact of using classification and subject index terms in bibliographic records for titles in the health subject area. The work of the group concentrated on two areas: -establishing a benchmark for throughput in Technical Services in terms of speed, cost and availability of externally supplied class numbers -analysis of differences in classification numbers and subject indexing terms between those human assigned and system assigned. Samples of data were analysed using SPSS software; a fuzzy matching process was undertaken for the subject string analysis. The results showed considerable savings to be made in terms of both speed and cost. lt was instrumental in the decision to change the existing method of acquiring classification numbers.The hit rate for records and the impact on the shelf arrangement were at an acceptable level. The study produced reliable information to provide a benchmark for future developments (for exarnple outsourcing shelf ready books) and performance indicators.

Ian Jennings, Dianne Kitchen, David Keeling, David Fitzmaurice and Carl Heneghan on behalf of the BCSH Committee UK NEQAS (Blood Coagulation), Sheffield, Oxford University Hospitals, Oxford Haemophilia and Thrombosis Centre, Churchill Hospital, Oxford, The University of Birmingham, Primary Care Clinical Sciences, Edgbaston, Birmingham, and Department of Primary Care Health Sciences, Oxford University, Oxford, UK

Summary. A World Federation of Hemophilia External Quality Assessment Scheme has been established to promote high standards of laboratory performance in haemophilia centres worldwide. Twenty-two International Haemophilia Training Centres (IHTCs) participated in a pilot study designed to assess between-laboratory agreement and to establish target values for the prothrombin time, activated partial thromboplastin time, factor VIII:C, IX:C and von Willebrand factor assays. Although variations in results and clinical interpretations were observed between the centres, median results and assay precision were comparable to that seen in the United Kingdom National External Quality Assessment Scheme. IHTC-generated median results were therefore considered appropriate target values against which to compare the performance of haemophilia centres in developing countries.

Introduction Although the variability in factor VIII (FVIII):C measurement is well recognized, this has not been widely reported for post-FVIII infusion samples. Aim/Methods Three samples from haemophilia A patients were distributed in a UK National External Quality Assessment Scheme survey, each after treatment with either ReFacto AF, Kogenate FS or Advate. Fifty-two UK haemophilia centres performed FVIII assays using one-stage (n = 46) and chromogenic (n = 10) assays. Centres calibrated assays with the local plasma standard and with ReFacto AF laboratory standard for the ReFacto AF sample. Results/Conclusions Chromogenic assays gave significantly higher results than one-stage assays (P < 0.0001, 32% difference) in the post-Kogenate sample but not in the post-ReFacto AF (11% higher by chromogenic assay, ns) or post-Advate samples (3% lower by chromogenic, ns) when assays were calibrated with plasma standards. Twenty centres used all Instrumentation Laboratory (IL)-activated partial thromboplastin time reagents (Synthasil)/IL deficient plasma/reference plasma) in the one-stage assay and 15 used all Siemens reagents (Actin FS/Siemens deficient plasma/reference plasma); this made a significant difference to results post-ReFacto AF (41% higher by IL reagents, P < 0.0001) and Advate (39% higher by IL reagents, P < 0.0001), but not Kogenate (7% higher by IL, ns) when calibrated with plasma standards. Differences between results obtained with different one-stage assay reagents for monitoring Advate have implications for dosing patients. Furthermore, there was considerable inter-laboratory variation as indicated by CVs in the range 15–26% for chromogenic assay and 12–19% for one-stage assay results. This study suggests that external quality assessment schemes should offer participation in post-FVIII infusion schemes where haemophilic patients are monitored.

Background Vitamin K antagonists have been used for many decades and have been traditionally monitored by the measurement of the International Normalised Ratio (INR) in the laboratory. Introduction of Point of Care (POC) testing devices to measure INR has resulted in many tests being undertaken in primary care. External Quality Assessment (EQA) of these POC devices is recommended to ensure accuracy and reliability of INR results outside a laboratory setting. Aim To assess the quality of INR results for users of two POC devices (CoaguChek XS and CoaguChek XS Plus) over a four-year period. Methods Four surveys (two samples) were sent in each 12-month period. The median INR value of each sample was calculated and the percentage deviation from this median determined. Any results greater than 15% from the median were considered to be outside consensus which indicated a possible problem within the testing system. Results Variability of INR results in this UK National External Quality Assessment Scheme (NEQAS) programme was comparable to that in the UK NEQAS EQA programme for laboratory INR testing. Occurrence of persistent problems was lower in the POC programme than the laboratory programme. Conclusions Utilisation of an EQA programme for POC devices in primary care is feasible and necessary. Our data suggest for those health professionals using EQA, the reliability and accuracy of INR testing matches the quality of laboratory testing.

von Willebrand disease (VWD) is the most common inherited bleeding disorder, but variable severity and several classification types mean that diagnosis is often not straightforward. In many countries, the assays are not readily available and/or are not well standardized. The latest methods and the basis of VWD are discussed here, together with information from the international quality assessment programme (IEQAS). Factor XIII deficiency is a rare, but important bleeding disorder, which may be missed or diagnosed late. A discussion and update on this diagnosis is considered in the final section of our review.

Congenital defects of platelets or plasma proteins involved in blood coagulation generally lead to bleeding disorders. In some of these disorders, patients with a severe phenotype are prone to spontaneous bleeds with critical consequences. This situation occurs more commonly in haemophilia A and haemophilia B and to a certain extent in severe forms (type 3) of von Willebrand disease. Defects in other plasma coagulation proteins and platelet factors are relatively rare, with an incidence of ≤ 1: 1-2 million. Molecular genetic studies of the human coagulation factors, especially factors VIII and IX, have contributed to a better understanding of the biology of these genetic disorders, the accurate detection of carriers and genetic counselling, and have also fostered new therapeutic strategies. This article reviews the evolution of genetics over the last five decades as a tool for bleeding disorder investigations, the recent advances in molecular techniques that have contributed to improved genetic diagnosis of this condition, and the development and utility of proficiency testing programmes and reference materials for genetic diagnosis of bleeding disorders.

Summary Introduction: The quality of anticoagulation management is not readily or frequently assessed, particularly between different centres. This study sought to evaluate agreement in oral anticoagulant management decisions between participating centres in UK NEQAS programmes. Methods: Participants were asked to indicate whether they used computerized dosing support software (CDSS) and to complete a series of questions with respect to anticoagulant management provision. Four clinical scenarios were provided, together with past and current International Normalised Ratio (INR) results. Participants were asked to provide recommendations on the target INR they would assign to the patient, the dose of warfarin and a recall interval. Results: Seven hundred and fifty-nine centres returned results, of which 28% were enrolled in the hospital-based EQA programme, and 72% were participants in the point-of-care testing programme. Six hundred (79%) reported use of CDSS. In one straightforward scenario, there was 99% agreement in dose recommendation. However, for three more complex scenarios, differences were apparent in target INRs employed and both dose and recall recommendations. In some cases, differences related to the software system employed. Conclusion: The study emphasizes large variation in the approach to managing these scenarios and warrants further investigation, together with education including promoting national guidelines for the assignment of target ranges.

Global hemostasis devices are currently being employed in operating rooms to assess the bleeding risk and outcomes for patients undergoing surgery. Two devices currently available are the TEG (Thromboelastograph; Haemoscope Corp., Niles, IL) and the ROTEM (Rotation Thromboelastometer; Pentapharm GmbH, Munich, Germany). Both measure the speed of clot formation, the strength of the clot when formed, and clot fibrinolysis kinetics. The two devices use different parameters so no cross comparisons of results can be made. The devices are usually operated by a member of the operating team and not a laboratory scientist; thus their testing and performance is generally not laboratory controlled, despite quality control being required to ensure reliable results. The UK National External Quality Assessment Scheme (NEQAS) for Blood Coagulation has undertaken a series of exercises evaluating the provision of External Quality Assessment (EQA) material for these devices. A series of four studies have taken place using lyophilized plasmas as the test material. Up to 18 TEG users and 10 ROTEM users have been involved in testing two samples per study, for a total of eight samples tested. The samples were normal plasmas, factor VIII or XI deficient samples, or normal plasmas spiked with heparin. The precision of the tests varied greatly for both devices, with coefficients of variances ranging from 7.1 to 39.9% for TEG and 7.0 to 83.6% for ROTEM. Some centers returned results that were sufficiently different from those obtained by other participants to predict alterations in patient management decisions. Our data indicate that regular EQA/proficiency testing is needed for these devices.

We report the results of external quality assessment exercises in which 60 to 120 centers performed factor VIII (FVIII) inhibitor testing on a series of samples over a 13-year period. Samples from seven different subjects were distributed for analysis comprising the following: four different subjects with severe hemophilia A with antibodies following replacement therapy, one subject with acquired hemophilia A and antibodies to FVIII, one subject with normal FVIII and an easily detected lupus anticoagulant, and one subject with mild hemophilia A and a difficult-to-detect lupus anticoagulant but without antibodies to FVIII. In all of the surveys the results obtained in different centers analyzing the same sample varied to an extent that would influence patient management decisions. In the UK National External Quality Assessment Scheme surveys reported here, there was considerable interlaboratory variation in the results of FVIII inhibitor testing that did not improve over the survey period. The coefficient of variation of results in different centers was between 33% and 106% in samples from patients with severe congenital hemophilia A. In some cases, results were affected by assay components. For one plasma, the mean FVIII inhibitor results in centers using one source of normal plasma was 3.9 Bethesda unit (BU)/mL compared with a mean of 5.7 BU/mL in centers using a different normal plasma source ( P = 0.04). Our data indicate that the detection of FVIII inhibitors is not the same in different centers, and the degree of variability noted makes it likely that assay variability has contributed to the lack of international consensus in relation to the real incidence of FVIII inhibitors in different clinical settings. Improvements in assay standardization are urgently needed.

Competitive balance is thought to be an important aspect of sport. Notions of ‘equity’ or ‘fair play’ appeal to the concept of competitive balance. Focusing upon the period between 1948 and 2008, this paper uses data from the top division of English football to investigate what has happened to competitive balance through the use of three measures. The first measure is an index, similar to a concentration ratio, that seeks to capture the extent to which the four most successful teams, by decade, have dominated the league. The second measure uses the Herfindahl index to discover the number of competitive teams in the league over the six decades. The final measure looks, season by season, at the probability of repeat success. The results suggest, from all three measures, that competitive balance has decreased and that the ‘beautiful game’ in England is in danger of becoming a monopoly of the few.

Summary. External quality assessment (EQA) has been shown to improve laboratory performance and diagnosis in haemostasis. We report here findings from the World Federation of Haemophilia (WFH) EQA programme during the period 2004–2007. Samples for PT, APTT, FVIII:C, FIX:C and VWF assays were distributed to centres in both established and emerging countries, and results were compared with results obtained by United Kingdom National External Quality Assessment Scheme (UK NEQAS) participants on the same samples. In general, good agreement was seen throughout between WFH and UK NEQAS for screening tests, and it was possible to identify an improvement in WFH centre agreement for results for VWF assays during the period of study. Agreement between emerging and established WFH centres was comparable for screening tests, possibly indicative of the relative simplicity of these tests and the degree of automation now employed in almost all haemostasis laboratories. However, CVs and performance compared with UK NEQAS participant results for factor assays amongst established centres was better than between emerging centres. Distribution of a questionnaire revealed different application of methodology for these assays, which may contribute to the observed difference in performance. Several centres participated in supplementary exercises, with comparable results obtained by emerging and established centres performing FVIII and fibrinogen measurement on cryoprecipitate, and all centres performing FVIII inhibitor assays correctly identifying the presence of an inhibitor. Participation in EQA programmes should continue to encourage improvement in laboratory performance and therefore improvements in the diagnosis and care of patients with haemophilia.

The essay examines the sources of the disquiet frequently expressed in the South African media at the predominantly white nature of the national cricket side. In particular, the authors focus on the argument which claims, first, that national sports teams must be representative, second, that the predominantly white nature of the national cricket side is unrepresentative and therefore unacceptable, and, finally, that the solution to the problem would be the enforcement of a racial quota whereby a certain number of players of colour must take the field each time the team plays. It is argued that although international sport does indeed derive its significance from the representivity of the national sides which take part, the sense of representivity appropriate to this context entails nothing in the way of ethnic profiles, but rather takes national sides which make up the strongest possible combination of all eligible players – players who are eligible on the basis of nationality and not ethnicity – to be pr...

SummaryAccurate and precise measurement of plasma D-dimer levels is important in the diagnosis and management of venous thromboembolism. Considerable variability in D-dimer results obtained using different methods has, however, been reported in multicentre studies. This study explored in two separate multicentre exercises the degree of precision amongst laboratory D-dimer measurements, and the degree by which inter-method agreement could be improved using a calibration curve model. The first exercise demonstrated generally good within-centre precision, with 82% of the centres reporting results for two identical but differently coded samples within 10% of each other. However, six centres reported results which would have excluded deep vein thrombosis (DVT) for one sample but failed to exclude DVT for the other, identical sample. In the second exercise, overall between-method precision of D-dimer results for two samples was shown to improve markedly when a calibration model was applied, using the consensus median values obtained by all participants for three “calibration plasmas” to recalculate D-dimer values. For centres reporting results in fibrinogen equivalent units (FEUs),between-centre coefficients of variation (CVs) fell from 25.9% to 11.6% and 22.4% to 7.7%, respectively, for the two samples. For centres reporting in ng/ml, CVs fell from 45.3–21.6% and 40.8–11.6%,respectively. In conclusion, improved harmonisation of D-dimer results by different methods may be achieved by a calibration model and common calibrant plasmas.

Point-of-care (POC) testing within hemostasis is an expanding field, with the most widely used test being POC international normalized ratio (INR). Many of these devices are being used in a nonlaboratory setting by staff with no laboratory training. In the United Kingdom, external quality assessment (EQA) is provided by the organization UK National External Quality Assessment Scheme for Blood Coagulation (UK NEQAS BC). Participants within the UK NEQAS BC POC INR program are largely based in primary care (77%), with the majority of EQA samples and patients tests being performed by nurses (70%). Many of these centers do not have support from the laboratory staff and may, therefore, not understand the requirement for a robust quality control (QC) system comprising both internal quality control (IQC) and EQA. From data acquired through a questionnaire of these UK NEQAS BC users, we observed that 2% of the centers never perform IQC tests, only 29% perform IQC tests when starting a new batch of test strips, and just 15% carry out IQC with each clinic as recommended by the UK guidelines. The imprecision of EQA tests was greater for POC users than in the UK NEQAS BC hospital laboratory program, with average coefficients of variation for a 2-year period of 11.0 and 7.3%, respectively. This may reflect the handling of EQA samples rather than the imprecision of the method, due to the lack of laboratory training amongst POC staff. POC INR in the UK could greatly benefit from more interaction and support from laboratories to these POC testers.

SummaryExternal quality assessment (EQA) or proficiency testing is widely considered to be necessary for International Normalised Ratio (INR) determinations performed in conventional laboratory settings. There is increasing use of near-patient-test (NPT) or point-of-care (POC) INR devices and it is not known whether EQA is also necessary for these monitors. We report here on six years experience of proficiency testing for POC monitors used by health care professionals. Three devices were used by >10 centres who participated in the programme, the CoaguChek (CUC), the CUC-S and the TAS or Rapidpoint Coag. Not all users of the same type of monitor obtained the same INR result when analysing the same plasma sample. For the three monitors the CV of results in different centres was 11–14%. The variation between results in different centres could relate to inappropriately handled proficiency testing material, inaccuracies in the calibration of the system by the manufacturer or deterioration during transport/storage of the test strips. In each survey 10–11% of centres using POC monitors obtained INR results which were >15% different from those in other centres using the same monitors. For hospital laboratories using conventional INR techniques this figure was 12%. The relationship between INR results obtained by users of the Rapidpoint Coag orTAS monitor and results obtained by conventional techniques was not constant over the period of study. During one period INRs with TAS were 13.7% greater than with conventional methods. For the remaining three time periods results were similar. Our data suggest that the variation between INR results determined with three POC monitors show similar variation to that observed in hospital laboratories using conventional methods. Based on our data we recommend that users of these POC monitors participate regularly in an independent external proficiency testing programme.

SummaryMolecular genetic analysis of families with haemophilia and other inherited bleeding disorders is nowa common laboratory investigation. In contrast to phenotypic testing in which strict quality control is adhered to, in haemophilia molecular genetic testing there has been a lack of any external quality assurance schemes. In 1998 the UK National External Quality Assessment Scheme (UK NEQAS) established a pilot quality assurance scheme for molecular genetic testing in haemophilia. Results from three initial surveys highlighted problems with the quality of samples when used to screen for the intron 22 inversion within the F8 gene. The scheme was re-launched in 2003, and since that time there have been five exercises involving whole blood or immortalised cell line DNA. The results together with an overall summary of the exercise are subsequently returned to participants. Exercises to date have focused exclusively on haemophilia A and QA, material has included screening for the intron 1 and intron 22 inversions as well as sequence analysis. A paper exercise circulated in 2003 highlighted problems with the format of reports and, following feedback to participants, onlya single error has been made in the subsequent four exercises. Participating laboratories now receive QA material every six months. Immortalised cell line material was introduced in 2005 and was shown to perform well. This will allow expansion of the scheme and a reduction in the dependence on blood donation.

We describe here results from the United Kingdom National External Quality Assessment Scheme (UK NEQAS) Thrombophilia Screening Program, in which an average of 21% of 280 centers reported an incorrect diagnosis for a series of plasma samples. Three case studies are described, showing causes of error in individual laboratories, related to the source of reference plasma or reagents. Methodological bias is also described. For protein C (PC) assays 18% of centers reported PC deficiency in a patient homozygous for factor V Leiden. Studies in the NEQAS laboratory confirmed the effect of activated protein C resistance (APCR) on clot-based PC activity assays. Differences in results obtained for PS-deficient subjects with different protein S (PS) activity kits are reported; several subjects would be misdiagnosed as normal with one kit if the manufacturer's reported reference range was adopted instead of a locally determined reference range. Antithrombin (AT) assays were shown to vary in their sensitivity to different molecular defects in the antithrombin gene; 77% of centers employing human thrombin-based activity assays reported a normal AT level in a patient with antithrombin Cambridge II. Sensitivity of the APC resistance test in the absence of factor V-deficient plasma was shown to be improved through normalization of results, and errors in the genetic diagnosis of factor V Leiden and the P20210A prothrombin gene mutation are described. Errors in the diagnosis of thrombophilic defects can therefore be identified through participation in EQA programs, and following dissemination of information, improvements in diagnosis can be demonstrated.

Thaddeus Metz's book Meaning in Life is, as he puts it, the culmination of 'more than a decade's reflection' (p. 249) on the subject, a good deal of it published, and it shows. It is a thoroughly argued, carefully constructed attempt, in the style of contemporary analytic philosophy, to ascertain what is meant when an individual person is judged to be living, or to have lived, a meaningful life. As such, it does credit to the genre.

Summary. Familial (F)XIII deficiency is an extremely rare bleeding disorder. In most laboratories the diagnosis is initially established through a clot-solubility screening test. We report here results from a series of UK NEQAS (Blood Coagulation). Proficiency Testing investigations, in which laboratories were provided with samples from normal individuals and from various subjects with FXIII deficiency with a request to perform their usual test for this disorder and to provide an interpretation of their results. Over 95% of centers were able to diagnose severe familial FXIII deficiency in previously untreated patients and to identify samples from normal subjects. However, both quantitative and qualitative methods produced widely variable results on samples obtained from previously treated individuals with FXIII deficiency but having measurable levels of FXIII. Data generated by UK NEQAS investigations suggested that solubility tests employing thrombin show greater sensitivity to FXIII deficiency, and this was confirmed in a subsequent single-center study. Our results lead us to recommend the use of thrombin and acetic acid in the clot-solubility screening test. Use of sensitive screening tests, and improvement in the accuracy and precision of quantitative FXIII assays will aid study of the clinical importance of moderate FXIII deficiency.

The role of external quality assessment (EQA) is a contentious issue for patient self-management (PSM) of oral anticoagulation. Patients from general practices in the West Midlands undertaking PSM were recruited to compare efficacy of patients' and health professionals' EQA procedure using the UK National External Quality Assessment Scheme (NEQAS). Patients using Coaguchek (Roche Diagnostics) were trained to perform EQA as part of their PSM training. They undertook PSM for 26 weeks and were asked to perform EQA using material provided by the UK NEQAS twice at home without supervision and twice at the practice with supervision. Patients' results were compared with health care professional users of Coaguchek S. Twenty-three PSM patients were compared with 75 health care professional users of the NEQAS scheme. The PSM group international normalized ratio (INR) percentage time in range was 74%. There was no significant difference in the median results on NEQAS samples obtained by the patients and those obtained by professionals. Three patients were outwith consensus (results > 15% from the median INR) on more than one occasion. Patients were able to perform the EQA tests competently. The data show that good agreement can be achieved between patients analysing the same EQA samples, with coefficients of variation ranging from 22.3% to as low as 5.4%. Further study is required to determine how precision within these EQA schemes relates to the stability of treatment in patients' management of their own anticoagulation.

The worldwide annual incidence of venous thrombosis is estimated at 1 in 1000 individuals, and associated pulmonary embolism represents a major cause of morbidity and mortality. Thrombophilia may be an inherited or acquired condition, with the former identified in approximately 25-30% of patients with thromboembolic disease. Recently published guidelines on thrombophilia testing recommend assays for protein C, protein S and antithrombin; a modified activated protein C resistance test (with factor V-deficient plasma); polymerase chain reaction for prothrombin G20201A, together with prothrombin time, activated partial thromboplastin time, thrombin clotting time and assays to detect antiphospholipid antibodies. This review highlights some of the issues that laboratories should consider when employing tests for the diagnosis of thrombophilia.

The 5th Haemophilia Global Summit was held in Barcelona, Spain, in September 2014. The programme was designed by an independent Scientific Steering Committee of haemophilia experts and explored issues relevant to the practical management of haemophilia, as well as key opportunities and challenges for care in the future. The topics outlined in this supplement were selected by the Scientific Steering Committee for their relevance to improving haemophilia care globally. In this supplement from the meeting, Gerry Dolan explores pharmacokinetics and dynamics in haemophilia, and Gerry Dolan and Ian Jennings jointly address the role of the laboratory in haemophilia care. The potential benefits of low-dose prophylaxis regimens for people with haemophilia in the developing world are reviewed by Jerzy Windyga, and the question of whether 'Future haemophilia research should be undertaken in the developing world' is debated by Jerzy Windyga and Cedric Hermans. Management strategies for ankle arthropathy are discussed by Sebastien Lobet and E. Carlos Rodriguez-Merchan, and the use of ultrasound for the early detection of haemophilic arthropathy is addressed by Matteo Nicola Dario Di Minno and Victor Jimenez-Yuste. Finally, the role of patients in the future of haemophilia care is reviewed by Brian O'Mahony.

Laboratory screening for lupus anticoagulant (LA) has been shown to be suboptimal in several studies. Guidelines have recently been published by an expert group for the British Committee for Standards in Haematology, in an attempt to standardize and improve screening procedures. The value of using screening tests conforming with these guidelines was investigated in a United Kingdom National External Quality Assessment Scheme (UK NEQAS) proficiency testing exercise. The correct diagnosis was achieved by 97% of laboratories for a LA-negative sample. However, 18.3% of centres reported a false-negative result for a sample from a LA-positive subject. A significantly higher proportion of centres that used methods conforming with the published guidelines achieved the correct diagnosis for this sample (P < 0.002, chi-square test). A wide variety of screening tests were used by laboratories in this study. Within-method agreement could be improved by the use of a common normal pooled plasma to determine ratios. However, between-method agreement was not improved by this procedure. We conclude that adoption of methods compliant with national guidelines may improve the diagnosis of LA. There is a need, however, for reference and standardization materials to ensure further improvement in the accuracy of LA methods.