External Quality Assessment in The Netherlands: time to introduce commutable survey specimens. Lessons from the Dutch “Calibration 2000” project

2005 ◽  
Vol 43 (3) ◽  
Author(s):  
Henk Baadenhuijsen ◽  
Aldy Kuypers ◽  
Cas Weykamp ◽  
Christa Cobbaert ◽  
Rob Jansen
Keyword(s):  
Reference Material ◽  
The Netherlands ◽  
Quality Assessment ◽  
External Quality Assessment ◽  
Accuracy Assessment ◽  
Reference Method ◽  
Field Method ◽  
External Quality ◽  
Wet Chemistry ◽  
Eqa Schemes

AbstractThe performance of suitable secondary reference material for the use of trueness control of six routinely measured clinical enzymes in the Dutch External Quality Assessment (EQA) scheme is described. The reference material of choice was selected using the split-patient-sample between-field method (twin study) design as described in an earlier study of the Calibration 2000 project in The Netherlands. This material, which was proven to be commutable for all wet chemistry systems, was implemented as the national enzyme calibrator. It consisted of a cryo-protected lyophilised serum with additions of recombinant human enzymes. Various batches of the frozen version of this material without cryo-protection additive, called native EQA samples, were used in the general EQA scheme for performance evaluation. The results of Calibration 2000 calibrated and non-Calibration 2000 calibrated laboratories were compared for both the regular (spiked with non-human enzymes) and native EQA samples in terms of precision and bias with established reference method values for the native samples. The regular samples showed mean between-laboratory CV ranges for all six enzymes involved (low–high) of 5.5–10.3% for the non-calibrated users vs. 4.6–10.8% for the calibrated users. For the native samples these respective ranges were 5.2–9.9% vs. 2.2–4.9%. Without exception, the group of Calibration 2000 calibrated users showed the lowest bias against the reference method values. Regular EQA samples (spiked with non-human enzymes) showed poorer performance than native samples and are not suitable for accuracy assessment purposes, the main aim of EQA schemes. Native samples that are commutable should be used for trueness control in current EQA schemes.

Harmonising EQA schemes the next frontier: challenging the status quo

2020 ◽  
Vol 58 (11) ◽  
pp. 1795-1797 ◽  
Author(s):  
Tony Badrick ◽  
Anne Stavelin
Keyword(s):  
External Quality Assessment ◽  
Reference Method ◽  
Laboratory Medicine ◽  
Status Quo ◽  
External Quality ◽  
Educational Support ◽  
Laboratory Results ◽  
The Status ◽  
Clinically Significant ◽  
Eqa Schemes

AbstractThere is a focus on standardisation and harmonisation of laboratory results to reduce the risk of misinterpretation of patient results assayed in different laboratories. External quality assessment (EQA) is critical to assess the need for harmonisation and to monitor the success of procedures to achieve harmonisation. However, EQA providers are being stretched to meet the needs of their participants with proven commutable material with reference method targets, a range of clinically significant levels of the materials, detailed and customised data analysis, and educational support. The path ahead for harmonisation of EQA schemes will require leadership from an organisation that has the support and confidence of EQA providers, like the European Organisation for External Qualily Assurance Providers in Laboratory Medicine.

Combi scheme: new combined internal/external quality-assessment scheme in The Netherlands

1991 ◽  
Vol 37 (7) ◽  
pp. 1196-1204 ◽  
Author(s):  
Herman Steigstra ◽  
Rob T Jansen ◽  
Henk Baadenhuijsen
Keyword(s):  
The Netherlands ◽  
Quality Assessment ◽  
Internal Control ◽  
External Quality Assessment ◽  
Clinical Chemistry ◽  
Laboratory Data ◽  
Data Communication ◽  
Professional Organization ◽  
Internal Quality ◽  
External Quality

Abstract The Dutch Foundation for Quality Assessment in Clinical Chemistry (SKZL) is the professional organization that conducts external quality-assessment schemes in The Netherlands. However, such schemes in fact assess the performance of the internal quality-control systems of the participating laboratories. In this paper we describe a new concept, relating the data for internal control materials with those for external samples and thereby leading to a combined external/internal scheme (Combi). The statistical principles underlying the Combi scheme are discussed and examples of the graphical presentation of the results are shown. Because the laboratory data are transmitted over the public telephone system to the computers of the SKZL, we also describe the principles of the data communication. At two-month intervals a statistical presentation is sent to all participants. The central database is updated daily with the received results, making possible an on-line consultation regarding the statistics of the accumulated findings of the control materials in use.

scholarly journals Results of the UK NEQAS for Molecular Genetics reference sample analysis

2018 ◽  
Vol 71 (11) ◽  
pp. 989-994 ◽  
Author(s):  
Susan D Richman ◽  
Jennifer Fairley ◽  
Jacqueline A Hall ◽  
Nakul Nataraj ◽  
Mrudul Bhide ◽  
...  
Keyword(s):  
Quality Assessment ◽  
Molecular Genetics ◽  
External Quality Assessment ◽  
Single Gene ◽  
Reference Sample ◽  
Human Cell Line ◽  
External Quality ◽  
Gene Testing ◽  
Variant Frequency ◽  
Eqa Schemes

AimsIn addition to providing external quality assessment (EQA) schemes, United Kingdom National External Quality Assessment service (UK NEQAS) for Molecular Genetics also supports the education of laboratories. As an enhancement to the Molecular Pathology EQA scheme, a human cell-line reference sample, manufactured by Thermo Fisher Scientific (AcroMetrix), was provided for analysis. This contained many variants, present at frequencies between 1% and 17.9%.MethodsOne hundred and one laboratories submitted results, with a total of 2889 test results on 53 genes being reported. Known polymorphisms, 46/2889 (1.59%) results, were excluded. Variants detected in the seven most commonly reported (and clinically relevant) genes, KRAS, NRAS, BRAF, EGFR, PIK3CA, KIT and PDGFRA, are reported here, as these genes fall within the scope of UK NEQAS EQA schemes.ResultsNext generation sequencing (NGS) was the most commonly performed testing platform. There were between 5 and 27 validated variants in the seven genes reported here. Eight laboratories correctly reported all five NRAS variants, and two correctly reported all eight BRAF variants. The validated mean variant frequency was lower than that determined by participating laboratories, with single-gene testing methodologies showing less variation in estimated frequencies than NGS platforms. Laboratories were more likely to correctly identify clinically relevant variants.ConclusionsOver 100 laboratories took the opportunity to test the ‘educational reference sample’, showing a willingness to further validate their testing platforms. While it was encouraging to see that the most widely reported variants were those which should be included in routine testing panels, reporting of variants was potentially open to interpretation, thus clarity is still required on whether laboratories selectively reported variants, by either clinical relevance or variant frequency.

The Preparation of Control Blood for External Quality Assessment Programs in Oral Anticoagulant Control

1978 ◽  
Vol 39 (01) ◽  
pp. 210-214 ◽  
Author(s):  
C A van Dijk-Wierda ◽  
L P van Halem-Visser ◽  
R van der Hoeff-van Halem ◽  
E A Loeliger
Keyword(s):  
Quality Control ◽  
The Netherlands ◽  
Quality Assessment ◽  
Oral Anticoagulant ◽  
External Quality Assessment ◽  
External Quality Control ◽  
External Quality ◽  
Blood Samples ◽  
Anticoagulant Agents

SummaryA method is described for the preparation of blood samples differing in coagulability, now used for external quality control in The Netherlands by laboratories employing thrombotest for the assessment of oral anticoagulant agents.

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.

scholarly journals External quality assessment for molecular diagnostic laboratories in Belgium: Can we improve it?

2019 ◽  
Vol 25 (1) ◽  
pp. 39-49
Author(s):  
Kelly Dufraing ◽  
Els Lierman ◽  
Anne Vankeerberghen ◽  
Sabine Franke ◽  
Els Dequeker
Keyword(s):  
Quality Assessment ◽  
Performance Monitoring ◽  
External Quality Assessment ◽  
Molecular Diagnostic ◽  
Real Patient ◽  
External Quality ◽  
Molecular Tests ◽  
Clinical Biology ◽  
Eqa Schemes ◽  
Selection Of

AbstractExternal quality assessment (EQA) is an essential part of performance monitoring for molecular laboratories. At the moment, a national law regulates participation in EQA schemes for clinical biology and pathology in Belgium. This study aimed (1) to get insights on how laboratories organize their EQA participation, (2) to poll satisfaction with the current situation (selection of EQA programs in advance by a governmental body), (3) to provide guidance for choosing the most relevant EQA provider and (4) to propose a new model for national performance monitoring. A survey was sent to Belgian laboratories performing molecular tests in the field of microbiology, hematology and pathology with (1) general questions on how they select an EQA provider and (2) their satisfaction of each provider. In total, 25 molecular laboratories [microbiology (N = 13), hematology (N = 8) and pathology (N = 4)] from 14 different hospitals completed the survey regarding their EQA organization. All three laboratory groups indicated to prefer EQA schemes using real patient materials as well as those with varying targets and concentrations. For molecular microbiology and hematology, schemes with a syndromic approach are sought. Since annual participation in EQA becomes burdensome in most laboratories, this paper also offers a risk-based strategy for determining the participation frequency. Based on the needs of Belgian laboratories, three proposals were made: (1) for the proper selection of an EQA scheme, (2) for determining the minimal participation frequency and (3) for the national organization of EQA schemes.

Quality Assessment of Tumor Marker Determinations: A Proposal for a Supraregional Scheme

1994 ◽  
Vol 9 (1) ◽  
pp. 48-52
Author(s):  
A. Piffanelli ◽  
M. Giganti ◽  
P. Colamussi ◽  
C. Cittanti ◽  
D. Pelizzola ◽  
...  
Keyword(s):  
Quality Assessment ◽  
Tumor Marker ◽  
Tumor Markers ◽  
External Quality Assessment ◽  
Clinical Chemistry ◽  
External Quality ◽  
Realistic Information ◽  
Eqa Schemes

The use of tumor marker tests has increased progressively in the last decade concomitant with the advent of new monoclonal antibodies and their growing use in clinical oncology for various follow-up programs. External quality assessment (EQA) schemes widely adopted in clinical chemistry, have been extended in the last decade to immunoassays of hormones and tumor markers. EQA results can provide realistic information on the quality of the assays, performed under routine conditions. The goal of this article is to report the main results and discrepancies encountered so far in External Quality Assessment programs on tumor markers.

External quality assessment (EQA) for CoaguChek monitors

2010 ◽  
Vol 103 (05) ◽  
pp. 936-941 ◽  
Author(s):  
Joergen Jespersen ◽  
A. M. H. P. van den Besselaar ◽  
Felix van der Meer ◽  
Gualtiero Palareti ◽  
Armando Tripodi ◽  
...  
Keyword(s):  
Quality Assessment ◽  
External Quality Assessment ◽  
Point Of Care ◽  
Concerted Action ◽  
External Quality ◽  
Test Strips ◽  
Italian Studies ◽  
Large Numbers ◽  
Treatment Procedures ◽  
Eqa Schemes

SummaryAnticoagulant control facilities are being overwhelmed by requests for monitoring and large numbers of patients are not therefore receiving treatment. Procedures designed for point-of-care testing have therefore been developed, the most popular being the CoaguChek. The need for external quality assessment (EQA) of monitors used by patients in self-management has been stressed in a European Commission (EC) Directive. It would not however be feasible for all CoaguChek monitors to be enrolled in national or regional EQA schemes which take time to organise and analyse. The European Concerted Action on Anticoagulation (ECAA) has therefore evolved a simpler system. Its value has been assessed in collaboration with the European Concerted Action on Thrombosis (ECAT). 523 monitors were tested at nine clinics which asked patients to bring their CoaguChek instruments to be assessed with the ECAA/ECAT procedure based on a set of 5 plasma samples with certified international normalised ratios (INR). 15% or more deviation from the certified INR on a single certified plasma sample from the set was defined by the ECAA as the limit of acceptable performance. One hundred and six (20.3%) of the monitors tested showed significant deviation and higher than average incidence of significant INR deviations reported with one specific numbered lot of test strips. Recent ECAA/ECAT, Danish and Italian studies report regular EQA of CoaguChek monitors is essential. There is general agreement that this should be performed at reasonably frequent intervals, at six months or whenever there is a change of the manufacturer’s test strips.

scholarly journals IFCC Working Group Recommendations for Assessing Commutability Part 2: Using the Difference in Bias between a Reference Material and Clinical Samples

2018 ◽  
Vol 64 (3) ◽  
pp. 455-464 ◽  
Author(s):  
Göran Nilsson ◽  
Jeffrey R Budd ◽  
Neil Greenberg ◽  
Vincent Delatour ◽  
Robert Rej ◽  
...  
Keyword(s):  
Reference Material ◽  
Quality Assessment ◽  
Working Group ◽  
External Quality Assessment ◽  
Clinical Samples ◽  
External Quality ◽  
Amount Of Substance ◽  
Specific Effects ◽  
Fit For Purpose ◽  
The Difference

Abstract A process is described to assess the commutability of a reference material (RM) intended for use as a calibrator, trueness control, or external quality assessment sample based on the difference in bias between an RM and clinical samples (CSs) measured using 2 different measurement procedures (MPs). This difference in bias is compared with a criterion based on a medically relevant difference between an RM and CS results to make a conclusion regarding commutability. When more than 2 MPs are included, the commutability is assessed pairwise for all combinations of 2 MPs. This approach allows the same criterion to be used for all combinations of MPs included in the assessment. The assessment is based on an error model that allows estimation of various random and systematic sources of error, including those from sample-specific effects of interfering substances. An advantage of this approach is that the difference in bias between an RM and the average bias of CSs at the concentration (i.e., amount of substance present or quantity value) of the RM is determined and its uncertainty estimated. An RM is considered fit for purpose for those MPs for which commutability is demonstrated.

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