Percorrer por autor "Weykamp, Cas"
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- Analytical performance of 17 general chemistry analytes across countries and across manufacturers in the INPUtS project of EQA organizers in Italy, the Netherlands, Portugal, United Kingdom and SpainPublication . Weykamp, Cas; Secchiero, Sandra; Plebani, Mario; Thelen, Marc; Cobbaert, Christa; Thomas, Annette; Jassam, Nuthar; Barth, Julian H.; Perich, Carmen; Ricós, Carmen; Faria, Ana PaulaBACKGROUND: Optimum patient care in relation to laboratory medicine is achieved when results of laboratory tests are equivalent, irrespective of the analytical platform used or the country where the laboratory is located. Standardization and harmonization minimize differences and the success of efforts to achieve this can be monitored with international category 1 external quality assessment (EQA) programs. METHODS: An EQA project with commutable samples, targeted with reference measurement procedures (RMPs) was organized by EQA institutes in Italy, the Netherlands, Portugal, UK, and Spain. Results of 17 general chemistry analytes were evaluated across countries and across manufacturers according to performance specifications derived from biological variation (BV). RESULTS: For K, uric acid, glucose, cholesterol and high-density density (HDL) cholesterol, the minimum performance specification was met in all countries and by all manufacturers. For Na, Cl, and Ca, the minimum performance specifications were met by none of the countries and manufacturers. For enzymes, the situation was complicated, as standardization of results of enzymes toward RMPs was still not achieved in 20% of the laboratories and questionable in the remaining 80%. CONCLUSIONS: The overall performance of the measurement of 17 general chemistry analytes in European medical laboratories met the minimum performance specifications. In this general picture, there were no significant differences per country and no significant differences per manufacturer. There were major differences between the analytes. There were six analytes for which the minimum quality specifications were not met and manufacturers should improve their performance for these analytes. Standardization of results of enzymes requires ongoing efforts.
- Behind the scenes of EQA – characteristics, capabilities, benefits and assets of external quality assessment (EQA): Part V – Benefits for stakeholders other than participantsPublication . Buchta, Christoph; De la Salle, Barbara; Marrington, Rachel; Aburto Almonacid, Andrés; Albarède, Stéphanie; Badrick, Tony; Bullock, David; Cobbaert, Christa M.; Coucke, Wim; Delatour, Vincent; Faria, Ana Paula; Geilenkeuser, Wolf-Jochen; Griesmacher, Andrea; Huggett, Jim F.; Ianovska, Viktoriia; Kammel, Martin; Kessler, Anja; Körmöczi, Günther F.; Meijer, Piet; Miranda, Armandina; Patel, Dina; Pezzati, Paola; Sandberg, Sverre; Schennach, Harald; Schweiger, Christian R.; Schwenoha, Karin; Spannagl, Michael; Sung, Heungsup; Thelen, Marc; Weykamp, Cas; Zeichhardt, Heinz; Restelli, Veronica; Perrone, Lucy A.External quality assessment (EQA) enhances patient safety through the evaluation of the quality of laboratory-based and point of care testing. Regulatory agencies and accreditation organizations utilize the results and the laboratory's response to them as part of assessing the laboratory's fitness to practice. In addition, where EQA samples are commutable and the assigned value has been determined using reference measurement procedures (RMPs), EQA data contributes to the verification of metrological traceability of assays as part of the post-market surveillance of diagnostic (IVD) medical devices (IVD-MDs). More broadly, the scientific and medical communities use EQA data to demonstrate that medical laboratory examination procedures are fit for clinical purposes, to evaluate common reference intervals, and inclusion of data in clinical databases. Scientific groups, the IVD industry, reference laboratories and National Metrology Institutes can work with EQA providers to identify measurands, which should urgently be supported by the development of reference materials or methods. The ability of health systems to respond effectively to fast-evolving medical challenges, such as the Coronavirus Disease-19 (COVID-19) pandemic, is reliant on EQA to demonstrate confidence in the performance of new laboratory methods and testing services. EQA providers are uniquely positioned to assess the performance of IVD-MDs in addition to individual laboratories and testing sites. Although the primary focus of EQA providers remains the improvement of the performance of individual laboratories, there are many stakeholders who benefit from EQA performance data.
- A category 1 EQA scheme for comparison of laboratory performance and method performance: An international pilot study in the framework of the Calibration 2000 projectPublication . Jansen, Rob; Nuthar, Jassam; Thomas, Annette; Perich, Carmen; Fernandez-Calle, Pilar; Faria, Ana Paula; Correia, Helena; Barth, Julian; Weykamp, Cas; Cobbaert, Christa; Thelen, Marc; Ricós, CarmenINTRODUCTION: In the modern healthcare service, patients receive care in multiple hospitals and healthcare settings. Therefore, harmonization of results from different methods and instruments, both between and within laboratories, is of the utmost importance. The present pilot study aims to test the use of a Category 1 EQA scheme across four European countries by assessing the current level of equivalence of test results. METHOD: This work was led by the Dutch External Quality Assurance Scheme SKML and involved 28 laboratories from three regions in the UK, Spain and Portugal, and 120 laboratories from The Netherlands. A set of six commutable samples, targeted with reference methods, were circulated and 18 biochemistry analytes were tested. RESULTS AND CONCLUSIONS: The Total Error (TE) score, defined as the probability (%) that results are within the Total Error Acceptable (TEA) limits, for the eighteen analytes was calculated. Our data show that there is a need for further harmonization of laboratory data, in particular for electrolytes (calcium, chloride, magnesium, sodium), enzymes (ALT, amylase, AST, LDH), lipids (HDL-cholesterol), and for substrates (creatinine, total protein). Lack of performance consistency between instruments was seen for most analytes. The lack of harmonization is still present despite manufacturer claims of established traceability.
- HbA1c laboratory quality performance of National External Quality Assessment Program (PNAEQ) in the EurA1c project: 2017–2024Publication . Correia, Helena; das Neves Pereira da Silva, Susana; Miranda, Armandina; Faria, Ana; Weykamp, Cas; Siebelder, CarlaIntroduction: The determination of glycated hemoglobin (HbA1c) is used in patients with diabetes mellitus as a key to monitoring the long-term blood glucose control (1). The Portuguese National External Quality Assessment Program (PNAEQ), organizes since 2003 the Hemoglobin glycated (HbA1c) program for External Quality Assessment Laboratory and integrated the IFCC EurA1c project in 2017. External Quality Assessment (EQA) is a powerful education tool to monitor quality that, by identifying poor performing laboratories and test systems, can be used as a tool to improve quality (2). Objective: Monitor the analytical performance of HbA1c determination, performed by PNAEQ participants, based on results of their participation in EurA1c project (bias (%) and coefficient of variation (CV%). Methods: From 2017 to 2024, PNAEQ laboratory participants (mean=41), from public and private sectors of ambulatory and hospital care, analysed in first round, two control samples per year, (n=16), with different concentrations (samples below and above 48mmol/mol). The samples sent from EurA1c project were lyophilized hemolysate specimens manufactured from the same pool. Participants HbA1c results, in IFCC units, were evaluated by comparison with target values assessed by EurA1c project. Usually, values were assigned by five laboratories using the IFCC Reference Measurement Procedure. The statistical analysis followed the EurA1c project´s methodology. Outliers- defined as results differing by more than 25% from the target value- were excluded prior to calculating the mean, CV% and bias%. Performance comparisons between different concentration samples were performed with Wilcoxon test considering a significance of 5%. Results: During the study period, an average of 41 laboratories participated (range: 26–49). A total of 17 different types of equipment and 9 distinct methodologies were used. From 2022 onwards, a noticeable shift in equipment and/or methodology was observed among several participants. Notably, five laboratories consistently submitted results for all samples throughout the study. There was no significant difference in the mean CV% between pathological samples (CV% = 5.1) and non-pathological samples (CV% = 5.7), with a p-value of 0.151. Similarly, no significant difference was observed in Bias% between pathological samples (Bias% = 1.0) and non-pathological samples (Bias% = 1.6), with a p-value of 0.069. Before pandemic period (2017-2019), the mean bias% was 0.02, in the pandemic period (2020-2021) was 3.18, and after pandemic 1.43. Based on the minimum EFLM quality specifications for HbA1c bias (2,7%), the mean bias of participants meets the established criteria in 13 samples. Regarding the desirable specification (1.8%), 10 samples and regarding the optimal specification (0.9%), 5 samples were compliant. During the pandemic period, 3 samples did not meet the minimum specifications. Conclusion: During the study period, the laboratories changed equipment without showing performance improvements. There is clear sign of a decline in performance in the pandemic period (2020-2022) with no improvement to the level of pre pandemic period. Most samples met the minimum quality specifications for HbA1c bias established by the EFLM, with a substantial proportion also meeting desirable and optimal targets. These findings highlight the effectiveness of the EurA1c external quality assessment framework in supporting continuous quality improvement in HbA1c testing across Portuguese laboratories.
- Post-standardization of routine creatinine assays: are they suitable for clinical applicationsPublication . Jassam, Nuthar; Weykamp, Cas; Thomas, Annette; Secchiero, Sandra; Sciacovelli, Laura; Plebani, Mario; Thelen, Marc; Cobbaert, Christa; Perich, Carmen; Ricós, Carmen; Paula, Faria A.; Barth, Julian H.Introduction Reliable serum creatinine measurements are of vital importance for the correct classification of chronic kidney disease and early identification of kidney injury. The National Kidney Disease Education Programme working group and other groups have defined clinically acceptable analytical limits for creatinine methods. The aim of this study was to re-evaluate the performance of routine creatinine methods in the light of these defined limits so as to assess their suitability for clinical practice. Method In collaboration with the Dutch External Quality Assurance scheme, six frozen commutable samples, with a creatinine concentration ranging from 80 to 239 μmol/L and traceable to isotope dilution mass spectrometry, were circulated to 91 laboratories in four European countries for creatinine measurement and estimated glomerular filtration rate calculation. Two out of the six samples were spiked with glucose to give high and low final concentrations of glucose. Results Results from 89 laboratories were analysed for bias, imprecision (%CV) for each creatinine assay and total error for estimated glomerular filtration rate. The participating laboratories used analytical instruments from four manufacturers; Abbott, Beckman, Roche and Siemens. All enzymatic methods in this study complied with the National Kidney Disease Education Programme working group recommended limits of bias of 5% above a creatinine concentration of 100 μmol/L. They also did not show any evidence of interference from glucose. In addition, they also showed compliance with the clinically recommended %CV of ≤4% across the analytical range. In contrast, the Jaffe methods showed variable performance with regard to the interference of glucose and unsatisfactory bias and precision. Conclusion Jaffe-based creatinine methods still exhibit considerable analytical variability in terms of bias, imprecision and lack of specificity, and this variability brings into question their clinical utility. We believe that clinical laboratories and manufacturers should work together to phase out the use of relatively non-specific Jaffe methods and replace them with more specific methods that are enzyme based.