scholarly journals EurA1c: The European HbA1c Trial to Investigate the Performance of HbA1c Assays in 2166 Laboratories across 17 Countries and 24 Manufacturers by Use of the IFCC Model for Quality Targets

2018 ◽  
Vol 64 (8) ◽  
pp. 1183-1192 ◽  
Author(s):  
◽  
Cas Weykamp ◽  
W Garry John ◽  
Emma English ◽  
Rajiv T Erasmus ◽  
...  
Keyword(s):  
Quality Assessment ◽  
Whole Blood ◽  
External Quality Assessment ◽  
State Of The Art ◽  
Total Error ◽  
Improve Quality ◽  
External Quality ◽  
Major Objective ◽  
Country Level ◽  
Blood Specimens

Abstract BACKGROUND A major objective of the IFCC Committee on Education and Use of Biomarkers in Diabetes is to generate awareness and improvement of HbA1c assays through evaluation of the performance by countries and manufacturers. METHODS Fresh whole blood and lyophilized hemolysate specimens manufactured from the same pool were used by 17 external quality assessment organizers to evaluate analytical performance of 2166 laboratories. Results were evaluated per country, per manufacturer, and per manufacturer and country combined according to criteria of the IFCC model for quality targets. RESULTS At the country level with fresh whole blood specimens, 6 countries met the IFCC criterion, 2 did not, and 2 were borderline. With lyophilized hemolysates, 5 countries met the criterion, 2 did not, and 3 were borderline. At the manufacturer level using fresh whole blood specimens, 13 manufacturers met the criterion, 8 did not, and 3 were borderline. Using lyophilized hemolysates, 7 manufacturers met the criterion, 6 did not, and 3 were borderline. In both country and manufacturer groups, the major contribution to total error derived from between-laboratory variation. There were no substantial differences in performance between groups using fresh whole blood or lyophilized hemolysate samples. CONCLUSIONS The state of the art is that 1 of 20 laboratories does not meet the IFCC criterion, but there are substantial differences between country and between manufacturer groups. Efforts to further improve quality should focus on reducing between-laboratory variation. With some limitations, fresh whole blood and well-defined lyophilized specimens are suitable for purpose.

External quality assessment in primary health care by using fresh whole blood

1994 ◽  
Vol 40 (12) ◽  
pp. 2223-2226 ◽  
Author(s):  
E Raabo ◽  
L Odum
Keyword(s):  
Primary Care ◽  
Quality Assessment ◽  
Whole Blood ◽  
Room Temperature ◽  
Matrix Effects ◽  
External Quality Assessment ◽  
Single Test ◽  
Control Material ◽  
External Quality ◽  
Primary Health

Abstract Desktop analyzers and single-test meters used in primary healthcare are mainly calibrated to measure whole blood. To minimize matrix effects of control materials in external quality assessment schemes, we stabilized fresh human EDTA-treated blood with sodium iodoacetate (1.8 mmol/L). The whole-blood based control material was useful for control of hemoglobin and glucose, the two most common analyses in primary care, even after storage at room temperature for at least 10 days and at 5 degrees C for 3 weeks. The material was also useful for control of cholesterol and creatinine analyses for samples stored as long as 3 days at ambient temperature.

Candidate reference methods for determining target values for cholesterol, creatinine, uric acid, and glucose in external quality assessment and internal accuracy control. I. Method setup

1993 ◽  
Vol 39 (6) ◽  
pp. 993-1000 ◽  
Author(s):  
D Stöckl ◽  
H Reinauer
Keyword(s):  
Uric Acid ◽  
Quality Assessment ◽  
External Quality Assessment ◽  
Total Error ◽  
Reference Method ◽  
Gas Chromatography Mass Spectrometry ◽  
Accuracy Control ◽  
External Quality ◽  
Reference Methods ◽  
Target Values

Abstract In Germany, the target values for External Quality Assessment (EQA) and internal accuracy control are determined by Reference Methods for several analytes, including cholesterol, creatinine, uric acid, and glucose. We present candidate Reference Methods for these compounds, based on isotope dilution-gas chromatography--mass spectrometry methods that have been developed at INSTAND, one of the two official Germany EQA reference institutions. Each Reference Method target value is calculated from six independent measurements performed on three different days. The mean method CVs ranged from 0.66% for glucose to 0.96% for creatinine. The inaccuracy (bias) of the methods is < 0.7%, as compared with the Standard Reference Material 909 of the National Institute of Standards and Technology. The maximum total error of a Reference Method value, including the 95% confidence interval and systematic errors, is < 2.3%. The presented candidate Reference Methods have been successfully used to set target values in the German EQA scheme and the internal accuracy control of routine laboratories.

National External Quality Assessment follow-up: 2010–2017 Turkish experience

2019 ◽  
Vol 44 (1) ◽  
pp. 1-8 ◽  
Author(s):  
Ferzane Mercan ◽  
Muhittin A. Serdar ◽  
Mehmet Senes ◽  
Dildar Konukoglu ◽  
Tamer Cevat İnal ◽  
...  
Keyword(s):  
Quality Assessment ◽  
External Quality Assessment ◽  
Total Error ◽  
Data Entry ◽  
Error Rates ◽  
Performance Ratio ◽  
External Quality ◽  
Significant Discrepancy ◽  
Technical Problems

Abstract Objective Medical laboratories encounter critical obstacles in External Quality Assessment (EQA) practices that are key to assessment of the analytical period. Present study aims to unveil the challenges in nationwide inter-laboratory harmonization and suggest practical solutions. Materials and methods EQA results of 1941 laboratories participating in 18 different EQA-programs between 2010 and 2017 were examined. Standard Deviation Index (SDI) of each program calculated using 801,028 sample data from 24 different clinical chemical tests were used to conduct a process assessment. Results There is a significant discrepancy in unsatisfactory performance ratio among different EAQ-programs with an average of 3.4% (27,074 cases) between 2010 and 2017 and a decreasing trend (~40–50%) in 7-years. Programs with higher SDI display lower discrepancy rates. Reasons for unaccepted results appear to be data entry errors (8.27–22.2%), material dilution errors (5–11.4%), technical problems (3.76–7.9%); while random or unidentified causes account for a major of 44.9–59.5%. In 7-years, 15.7% reduction was observed in average SDI of all tests. Conclusion With the launch of national EQA follow-up program, increased awareness of the analytical processes led to a decrease in unaccepted results and variances in the analytical period. Staff training is suggested as a significant measure. In addition, simultaneous assessment of SDI and allowable total error rates would reduce the variation between programs.

scholarly journals Comparison of Procedures for Evaluating Laboratory Performance in External Quality Assessment Schemes for Lead in Blood and Aluminum in Serum Demonstrates the Need for Common Quality Specifications

2002 ◽  
Vol 48 (11) ◽  
pp. 2000-2007 ◽  
Author(s):  
Andrew Taylor ◽  
Jurgen Angerer ◽  
Francoise Claeys ◽  
Jesper Kristiansen ◽  
Olav Mazarrasa ◽  
...  
Keyword(s):  
Quality Assessment ◽  
External Quality Assessment ◽  
Total Error ◽  
Blood Lead ◽  
External Quality ◽  
Target Concentration ◽  
Laboratory Performance ◽  
Environmental Laboratory ◽  
Z Scores ◽  
Quality Specifications

Abstract Background: The different scoring methods used by eight European External Quality Assessment Schemes (EQASs) for occupational and environmental laboratory medicine were compared to develop suitable quality specifications as a step toward harmonization. Methods: Real results for blood lead and serum aluminum assays, reported by participants in Italian and United Kingdom EQASs, were evaluated according to individual scheme scoring criteria. The same results were then used to produce z scores using scheme-based between-laboratory SDs as the estimate of variability to determine whether simple performance-derived quality specifications produced better agreement among schemes. Results: The schemes gave conflicting assessments of participants’ performance, and participants judged to be successful by one scheme could be defined as performing inadequately by another. An approach proposed by Kenny et al. (Scand J Clin Lab Invest 1999;59:585), which uses clinical inputs to set targets for analytical imprecision, bias, and total error allowable, was then used to elaborate quality specifications. Conclusions: We suggest that the CLIA ′88 recommendations for blood lead (± 40 μg/L or ± 10% of the target concentration, whichever is the greater) could be used as a quality specification, although a revision to ± 30 μg/L or ± 10% is recommended. For serum aluminum, a suitable quality specification of ± 5 μg/L or ± 20% of the target concentration, whichever is the greater, is suggested. These specifications may be used to compare laboratory performance across schemes.

External Quality Assessment/Proficiency Testing and Internal Quality Control for the PFA-100 and PFA-200: An Update

2014 ◽  
Vol 40 (02) ◽  
pp. 239-253 ◽  
Author(s):  
Emmanuel Favaloro ◽  
Roslyn Bonar
Keyword(s):  
Quality Control ◽  
Quality Assessment ◽  
Platelet Function ◽  
Whole Blood ◽  
External Quality Assessment ◽  
Internal Quality ◽  
External Quality ◽  
Platelet Function Testing ◽  
Primary Hemostasis ◽  
Function Testing

Platelet function testing is an essential component of comprehensive hemostasis evaluation within the framework of bleeding and/or bruising investigations, and it may also be performed to evaluate antiplatelet medication effects. Globally, the platelet function analyzer (PFA)-100 (Siemens Healthcare, Marburg, Germany) is the most used primary hemostasis-screening instrument and has also been recently remodeled/upgraded to the PFA-200. The PFA-100 is sensitive to a wide range of associated disorders, including platelet function defects and von Willebrand disease (VWD), as well as to various antiplatelet medications. The PFA-100 is also useful in therapy monitoring, especially in VWD. External quality assessment (EQA) (or proficiency testing) and internal quality control (IQC) are critical to ensuring quality of test practice, inclusive of all hemostasis tests. However, both EQA and IQC for platelet function testing, including the PFA-100, is logistically challenging, given theoretical requirements for production, storage, and shipment of large volumes of “stabilized” normal and pathological blood/platelets covering both normal function plus a wide variety of potential defects. We accordingly describe the development and testing of novel feasible approaches to both EQA and IQC of PFA-100/PFA-200 instruments, whereby a range of formulated “platelet function antagonist” materials are utilized. For EQA purposes, these are distributed to participants, and citrated normal whole blood collected on site is then added locally, thereby creating test material that can be locally evaluated. Several exercises have been conducted by the Royal College of Pathologists of Australasia Quality Assurance Program (RCPAQAP) over the past 6 years. A total of 26 challenges, with most designed to mimic moderate to severe primary hemostasis defects, have been tested in 26 to 50 laboratories depending on the year of dispatch. Numerical results for PFA-100/PFA-200 closure times (CTs) and interpretive comments supplied by participants are analyzed by the RCPAQAP. During this period, reported CTs for each challenge were within limits of expectation and good reproducibility was evidenced by repeated challenges. Coefficients of variation (CVs) generated for challenges using the two major PFA-100/PFA-200 cartridge types (collagen/adenosine diphosphate and collagen/epinephrine) are always similar to those obtained using native whole blood, and in general range from 15 to 25%. Interpretations are also in general consistent with expectations and test data provided by laboratories. The EQA created material has also been assessed within the context of possible IQC material. In conclusion, EQA and IQC processes for the PFA-100/PFA-200 have been developed that include highly reproducible test challenge processes, not only supporting the concept that EQA/IQC is possible for platelet function testing but also providing a valuable mechanism for monitoring and improving laboratory performance in this area.

scholarly journals K.06 QCMD: state of the art molecular external quality assessment for sexually transmitted pathogens

2009 ◽  
Vol 44 ◽  
pp. S2-S3
Author(s):  
W.G. MacKay ◽  
H.G.M. Niesters ◽  
J. Schirm ◽  
P.S. Wallace ◽  
A.M. van Loon
Keyword(s):  
Quality Assessment ◽  
External Quality Assessment ◽  
State Of The Art ◽  
External Quality ◽  
Sexually Transmitted

scholarly journals Commutability of a Whole-Blood External Quality Assessment Material for Point-of-Care C-Reactive Protein, Glucose, and Hemoglobin Testing

2019 ◽  
Vol 65 (6) ◽  
pp. 791-797 ◽  
Author(s):  
Tone Bukve ◽  
Sverre Sandberg ◽  
Wenche S Vie ◽  
Una Sølvik ◽  
Nina G Christensen ◽  
...  
Keyword(s):  
Quality Assessment ◽  
Whole Blood ◽  
External Quality Assessment ◽  
Point Of Care ◽  
C Reactive Protein ◽  
External Quality ◽  
Reactive Protein ◽  
Target Value ◽  
Reference Target ◽  
Deming Regression

Abstract BACKGROUND The optimal situation in external quality assessment (EQA) is to use commutable materials. No previous study has examined the commutability of a whole-blood material for point-of-care (POC) testing. The aim of this study was to determine the commutability of the Norwegian Quality Improvement of Laboratory Examinations (Noklus) organization's “in-house” whole-blood EQA material for C-reactive protein (CRP), glucose, and hemoglobin for frequently used POC instruments in Norway and to determine the possibility of using a common target value for each analyte. METHODS The study was performed according to the Clinical and Laboratory Standards Institute guidelines. The EQA material was pooled stabilized EDTA venous whole-blood containing different concentrations of the analytes. The EQA material and native routine patient samples were analyzed using 17 POC and 3 hospital instruments. The commutability was assessed using Deming regression analysis with 95% prediction intervals for each instrument comparison. RESULTS The EQA material was commutable for all CRP and hemoglobin POC instruments, whereas for glucose the material was commutable for all POC instruments at the lowest concentration analyzed [126.0 mg/dL (7.0 mmol/L)] and for 3 POC instruments at all of the concentrations analyzed. CONCLUSIONS Noklus EQA participants using CRP and hemoglobin POC instruments now receive results that are compared with a reference target value, whereas the results for participants using glucose POC instruments are still compared with method-specific target values. Systematic deviations from a reference target value for the commutable glucose POC instruments can be calculated, and this additional information can now be offered to these participants and to the manufacturers.

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