Participation In Interlaboratory Comparisons Research Articles

An inter-laboratory comparison between 13 international laboratories for eight components relevant for hydrogen fuel quality assessment

The quality of the hydrogen delivered by refuelling stations is critical for end-users and society. The purity of the hydrogen dispensed at hydrogen refuelling points should comply with the technical specifications included in the ISO 14687:2019 and EN 17124:2022 standards. Once laboratories have set up methods, they need to verify their performances, for example through participation in interlaboratory comparisons. Due to the challenge associated with the production of stable reference materials and transport of these which are produced in hydrogen at high pressure (>10 bar), interlaboratory comparisons have been organized in different steps, with increasing extent.This study describes an inter-laboratory comparison exercise for hydrogen fuel involving a large number of participants (13 laboratories), completed in less than a year and included eight key contaminants of hydrogen fuel at level close to the ISO14687 threshold. These compounds were selected based on their high probability of occurrence or because they have been found in hydrogen fuel samples. For the results of the intercomparison, it appeared that fully complying with ISO 21087:2019 is still challenging for many participants and highlighted the importance of organising these types of exercises. Many laboratories performed corrective actions based on their results, which in turn significantly improved their performances.

Monitoring the work of the test laboratory by participating in the proficiency testing program in the field of the laser performance measurements

Monitoring the validity result is the critical requirement of the international standard ISO/IEC 17025:2017 for test and calibration laboratories to provide objective evidence of their technical competence. Applying the interlaboratory comparison, using alternative instrumentation that has been calibrated, functional checks of measuring and testing equipment, and other methods for monitoring the validity of results is not enough to have confidence in the quality of test results. Modern standards in the field of quality for test and calibration laboratories require applying other forms for assessing the characteristics of the used test method. Particularly, it concerns the participation in interlaboratory comparisons.
 One of the tools that could be used for monitoring the validity result is comparing laboratory test results with the results that are obtained by other laboratories, e.g. proficiency testing. This paper presents the result of a proficiency testing program for laser performance measurements that was organized by the International provider IFM Quality Services PTY Ltd. in 2021. The purpose of the paper is to demonstrate the results of the participation of the SE “Ukrmetrteststandard” in proficiency testing of measuring laser performance, to reveal the correlation of the results comparing with the previous years and different tasks and to assess the possible causes of outliers. Twenty-two laboratories that had been accredited by the ISO/IEC 17025 standard participated in the proficiency testing. The results were evaluated using the Z-score as the performance criterion.
 Potential risks of proficiency testing with a small number of participants and possible causes of results outliers were assessed.

Quality assurance for the tests to determine explosive parameters of the combustible dust-air mixtures

For any type of combustible dust, several important explosive parameters must be taken into account when designing and using protection systems: namely the ease with which dust clouds ignite and their burning rate, maximum explosion pressure, maximum pressure rise speed. of explosion. The accuracy of the results obtained necessary for the design and use of protection systems depends on a number of factors but also on the accuracy of the application of the test method (s) by the personnel involved. Test quality assurance is a requirement of EN ISO / IEC 17025 for the accreditation of testing laboratories. The standard requires laboratories to have a procedure in place to monitor the validity of test results, which involves participation in interlaboratory comparisons. This paper presents some specific issues highlighted during the successful participation of INSEMEX-GLI in several rounds of interlaboratory comparisons for the tests to determine explosive parameters of the combustible dust-air mixtures.

Inter-laboratory Comparisons and Their Roles in Accreditation

Results of interlaboratory comparisons and proficiency tests are a significant parameter for the calibration and testing laboratories for assuring the quality of test and calibration results performed by those laboratories. If test and calibration laboratories want to demonstrate that they operate according to a management system, that they are technically competent and that they can produce technically valid results in the tests and calibrations they perform for their customers, the general requirements they must meet are defined in ISO/IEC 17025:2017. This international standard forms the basis of international laboratory accreditation. Clause 7.7 Ensuring the validity of results in this standard requires laboratories to establish the procedures and instructions and other technical documentation needed to ensure the results of the tests and calibrations they perform. Participation in inter-laboratory comparison or proficiency testing programs is one of the most important of these activities. Participation in inter-laboratory comparisons provides an opportunity for laboratories to independently evaluate their analytical performance, both in absolute terms and in comparison, to other techniques. In this study, information about calibration laboratories and accreditation activities is given and the importance of inter-laboratory comparison studies is explained to ensure the results of the measurements made by calibration laboratories.

MSI testing

Based on new trial data regarding immune checkpoint inhibitors (ICIs), the detection of high-grade microsatellite instability (MSI-H) or underlying deficient mismatch repair protein (dMMR) is now becoming increasingly important for predicting treatment response. For the first time, aPD‑1 ICI (pembrolizumab) has been approved by the European Medicines Agency (EMA) for first-line treatment of advanced (stageIV) dMMR/MSI‑H colorectal cancer (CRC). Further indications, such as dMMR/MSI‑H endometrial carcinoma (EC), have already succeeded (Dostarlimab, 2nd line treatment) and others are expected to follow before the end of 2021. The question of optimal testing in routine diagnostics should therefore be re-evaluated. Based on aconsideration of the strengths and weaknesses of the widely available methods (immunohistochemistry and PCR), atest algorithm is proposed that allows quality assured, reliable, and cost-effective dMMR/MSI‑H testing. For CRC and EC, testing is therefore already possible at the primary diagnosis stage, in line with international recommendations (NICE, NCCN). The clinician is therefore enabled from the outset to consider not only the predictive but also the prognostic and predispositional implications of such atest when counseling patients and formulating treatment recommendations. As abasis for quality assurance, participation in interlaboratory comparisons and continuous documentation of results (e.g., QuIP Monitor) are strongly recommended.

MSI testing : What is new? What should be considered? German version

Based on new trial data regarding immune checkpoint inhibitors (ICIs), the detection of high-grade microsatellite instability (MSI-H) or underlying deficient mismatch repair protein (dMMR) is now becoming increasingly important for predicting treatment response. For the first time, aPD‑1 ICI (pembrolizumab) has been approved by the European Medicines Agency (EMA) for first-line treatment of advanced (stageIV) dMMR/MSI‑H colorectal cancer (CRC). Further indications, such as dMMR/MSI‑H endometrial carcinoma (EC), have already succeeded (Dostarlimab, 2nd line treatment) and others are expected to follow before the end of 2021. The question of optimal testing in routine diagnostics should therefore be re-evaluated. Based on aconsideration of the strengths and weaknesses of the widely available methods (immunohistochemistry and PCR), atest algorithm is proposed that allows quality assured, reliable, and cost-effective dMMR/MSI‑H testing. For CRC and EC, testing is therefore already possible at the primary diagnosis stage, in line with international recommendations (NICE, NCCN). The clinician is therefore enabled from the outset to consider not only the predictive but also the prognostic and predispositional implications of such atest when counseling patients and formulating treatment recommendations. As abasis for quality assurance, participation in interlaboratory comparisons and continuous documentation of results (e.g., QuIP Monitor) are strongly recommended.

Quality assurance of test results for the determination of Ingress Protection Code for Ex equipment enclosures

INSEMEX-OEC is a Conformity Assessment Body for certification activities in accordance with ATEX Directive 2014/34/EU, being accredited by RENAR and notified to Brussels (NB1809). INSEMEXGLI (Group of Testing Laboratories) is the main provider of laboratory testing services for the product certification body INSEMEX-OEC. The test laboratories meet the requirements of the standard SR EN ISO / IEC 17025. This standard requires laboratories to have a procedure in place to monitor the validity of the test results. This monitoring must be planned and, if possible, should include participation in inter-laboratory comparisons or proficiency testing programs. This paper presents some specific issues highlighted during the successful participation of INSEMEX-GLI in a round of inter-laboratory comparisons organized by the Physikalisch-Technische Bundesanstalt from Germany to determine International Protection Code (IP Code) for equipment enclosures.

Proficiency testing and ring trials.

The validation of diagnostic methods (and the subsequent results generated by a laboratory) are improved through participation in inter-laboratory comparisons (IC), such as proficiency-testing (PT) programmes and other exercises referred to as 'ring tests' or 'ring trials' (RTs). This is a requirement to comply with international quality standards. Validating a method is a continuous process and taking part in ongoing PT programmes supports the management of a method's life cycle, providing continuing assessment of fitness (sometimes referred to as the 'validation retention status'). Proficiency-testing panel designs ensure that the methods used, particularly diagnostic specificity and sensitivity, are suitably challenged. Appraising PT results over time can illustrate whether the laboratory's performance is stable, improving or worsening, and proficiency tests can also highlight variations in the performance of assays. The development of new proficiency tests can support the implementation of novel diagnostics technologies, such as whole genome sequencing and point-of-care testing, and assist in cross-sectoral partnerships focusing on One Health approaches, which are high on the agenda for infectious disease control. For example, the rapid design and distribution of emergency exempted assays for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) means that these assays were not as rigorously evaluated as assays for established infectious diseases. Therefore, participation in PT programmes for SARS-CoV-2 is essential to understand the performance of these assays. While other mechanisms help to underpin laboratory activities, PT has been, and should remain, an integral part of laboratory quality assurance. Resources must be directed towards increasing and improving the quality of PT (for example, availability and accessibility of suitable biological and reference materials are essential for a PT provider to execute its duties), to support established and novel methods such as genomic and point-of-care tests.

Evaluation of veterinary laboratory proficiency based on results of interlaboratory comparisons organized by FGBI “ARRIAH” in 2018–2019

Laboratory diagnosis is a crucial component in implementation of the set of anti-epidemic measures aimed at contagious animal disease control. The need for unswerving trust in the quality of laboratory performance is a matter of importance not only for service providers and customers, but also for inspecting organiza­tions, accreditation bodies, etc. that establish performance requirements for diagnostic laboratories. Incorrect laboratory test results can lead to a misdiagnosis and, therefore, to grave consequences. One of the forms of experimental verification of a laboratory’s performance with a view to determine the laboratory’s competence and to verify its compliance with accreditation criteria as part of inspection control of the laboratory’s activities is interlaboratory comparison. The laboratory can prove its competence at a particular time, as well as clearly demonstrate how stable the quality of its test results is by summarizing and analyzing the results of its participation in interlaboratory comparisons. The analysis of the results of the interlaboratory comparisons (programmes for detection of causative agents or antibodies to the causative agents of avian influenza, Newcastle disease, rabies, classical swine fever, African swine fever, bluetongue, lumpy skin disease) organized by the FGBI “ARRIAH” for the veterinary laboratories of the Russian Federation in 2018–2019 is presented. The results showed that most of the laboratories had passed the tests successfully. The results submitted by participants were unsatisfactory in some interlaboratory comparison programmes (rabies virus detection using fluorescent antibody technique; detection of avian influenza, classical swine fever and lumpy skin disease viruses using polymerase chain reaction). That highlights the need for those participants who failed the tests to improve their laboratory testing quality.

Evaluación de la calidad de la medición de carbono total en suelo mediante ensayo de intercomparación.

The Mexican regulation NMX-EC-17025-IMNC-2006, establishes that laboratories must have quality control procedures to monitor the validity of tests and calibrations, such monitoring must be planned and reviewed with: a) the regular use of certif ied reference materials or internal quality control of secondary references; b) participation in inter-laboratory comparisons or a prof iciency testing program; c) the repetition of tests or calibrations using the same method or different methods; d) the repetition of the test or the calibration of determined objects; e) the correlation of results for different characteristics of a reference material certif ied by MRC. The quality evaluation of results from the eight laboratories of the Laboratory Network for Analysis, Use, Conservation and Management of Soil (REDLABS) included the elements of sections a), b), c), and d) in order to verify the hypothesis that laboratories emit repeatable, reproducible and unbiased results. In our study, elemental analyzers of different brands were used to measure the total carbon of soil. A certif ied reference material was included in the Inter-comparison Practice. Repeatability and reproducibility of the carbon analyzes were evaluated with samples from the inter-comparison practice; the precision of analyzes from each laboratory was qualif ied with MRC. The results obtained indicate that the laboratories show repeatability in their analyzes with no statistical differences, i.e. reproducibility is detected by inter-comparison. The data issued by the laboratories were unbiased according to their evaluation with certif ied reference material.

External quality assessment programs in the context of ISO 15189 accreditation.

AbstractEffective management of clinical laboratories participating in external quality assessment schemes (EQAS) is of fundamental importance in ensuring reliable analytical results. The International Standard ISO 15189:2012 requires participation in interlaboratory comparison [e.g. external quality assessment (EQA)] for all tests provided by an individual laboratory. If EQAS is not commercially available, alternative approaches should be identified, although clinical laboratories may find it challenging to choose the EQAS that comply with the international standards and approved guidelines. Great competence is therefore required, as well as knowledge of the characteristics and key elements affecting the reliability of an EQAS, and the analytical quality specifications stated in approved documents. Another skill of fundamental importance is the ability to identify an alternative approach when the available EQAS are inadequate or missing. Yet the choice of the right EQA program alone does not guarantee its effectiveness. In fact, the fundamental steps of analysis of the information provided in EQA reports and the ability to identify improvement actions to be undertaken call for the involvement of all laboratory staff playing a role in the specific activity. The aim of this paper was to describe the critical aspects that EQA providers and laboratory professionals should control in order to guarantee effective EQAS management and compliance with ISO 15189 accreditation requirements.

First Interlaboratory Comparison on Calibration of Temperature-Controlled Enclosures in Turkey

The number of accredited laboratories in the field of calibration of temperature-controlled enclosures has been increasing in Turkey. One of the main criteria demonstrating the competence of a calibration laboratory is successful participation in interlaboratory comparisons. Therefore, TUBITAK UME Temperature Laboratory organized the first interlaboratory comparison on “Calibration of Temperature-Controlled Enclosures” in Turkey as a pilot laboratory between January and November, 2013. Forty accredited laboratories which provide routine calibration services to the industry in this field participated in the comparison. The standards used during the comparison was a climatic chamber for the measurements at $$-40\, {^{\circ }}\hbox {C},\,-20\, {^{\circ }}\hbox {C}, 40\, {^{\circ }}\hbox {C}$$ and $$100\, {^{\circ }}\hbox {C}$$ and an oven for the measurements at $$200\, {^{\circ }}\hbox {C}$$ . The protocol of the comparison was prepared considering guide EURAMET cg-20 and BS EN/IEC standards 600068-3-5 and 600068-3-11. During the comparison measurements, each participant had the liberty to choose the most convenient calibration points in terms of their accreditation scope among the values mentioned above and carried out on-site measurements at UME. The details and the results of this comparison are given in the paper. Determination of the statistical consistency of the results with the uncertainties given by the participants can be assessed by the method of $$E_{n}$$ value assessment for each laboratory. $$E_{n}$$ values for all measurement results based on the results of pilot and participating laboratories were calculated.

134. QUALITY AND CONFIDENCE ASSURANCE IN ELECTRICAL QUANTITIES MEASUREMENTS – RESULTS OF FEIT–HTT INTER-LABORATORY COMPARISON

According to ISO/IEC 17025 a laboratory shall have quality control procedures for monitoring the validity of tests and calibrations undertaken, through participation in inter-laboratory comparisons (ILC) or profi-ciency testing programmes (PT). This practice should be a periodic activity and in accordance with the international standards. In the paper the results of the international ILC conducted by the Laboratory of Electrical Measurements (LEM) of the Faculty of Engineering and Information Technologies at the Ss. Cyril and Methodius University in Skopje, R. Macedonia (pilot laboratory), and the High Tech Test shpk – Tirana, R. Albania (HTT), both accredited laboratories, will be presented. The ILC accomplished in the period March–April 2017 was conducted through cali-bration of 6½ digital multimeter Keysight 34401A for various electrical quantities. In the paper, the detailed meas-urement procedure followed by the two laboratories as well as the evaluation and acceptance criteria will be given. The results of the ILC will be presented and discussed. The ILC gives a significant contribution the quality and con-fidence assurance in electrical quantities measurements at national and regional/international level.

The role of interlaboratory comparative tests/interlaboratory comparisons in the development of national, competitive products

Confidence in the quality of products, which were produced by the enterprise, is the key of success and competitiveness in the market. Confirming products’ quality and environmental security of the manufacture is impossible without a well-functioning testing and calibration laboratories, which can provide the accuracy of their results.Now, external evaluation of the laboratories’ competence by proficiency testing is one of the main instruments of development of laboratories’ activities and improving the quality of researches. Even with a perfectly functioning management system, high-precision expensive equipment and professional operators, without external evaluation laboratories can work for a long period with an offsets or significant random variations in measurement results. Only through proficiency testing, laboratories can reveal the presence of this kind of problem. Participation in Interlaboratory comparisons makes it possible to identify the "weak" sides of the laboratory operation and the successful implementation of preventive and corrective actions make them more "strong."

Redesign of a soft conductive rubber strip electrode for measurement of surface resistance according to IEC 60079-32-2 within the context of the PTB Ex Proficiency Testing Scheme

To ensure worldwide quality and homogeneity in the field of explosion protection, not only uniform rules in the form of IEC standards but also the active participation in interlaboratory comparisons are necessary. The “PTB Ex Proficiency Testing Scheme” is the first global proficiency testing program of its kind in the field of explosion protection. It serves as proof of competence and provides laboratories with a complete system for their own performance evaluation.In 2015, the program “Electrostatic Charge - Test Round 2015” was launched within the PTB Testing Scheme. The participants of the program performed surface resistance and transferred charge tests according to IEC 60079-0 and IEC 60079-32-2 on various types of test samples. The new standard IEC 60079-32-2 proposes different kinds of electrodes for the user, such as conductive silver paint electrodes, soft conductive rubber strip electrodes on spring-mounted metal tongues or conductive foam strips mounted on an insulating support, depending on the geometry of the sample. These different types of electrodes as well as the construction latitude for each electrode could lead to deviations between the results of different test laboratories due to better or worse electrode contact with the test sample.Therefore, the proficiency team and electrostatic experts at PTB decided to design an accurate and user-friendly electrode which meets the requirements of IEC 60079-32-2. This paper provides information about the electrodes' design as well as the results of comparable measurements.

QUALITY AND CONFIDENCE ASSURANCE IN ELECTRICAL QUANTITIES MEASUREMENTS – RESULTS OF FEIT–HTT INTER-LABORATORY COMPARISON

According to ISO/IEC 17025 a laboratory shall have quality control procedures for monitoring the validity of tests and calibrations undertaken, through participation in inter-laboratory comparisons (ILC) or profi-ciency testing programmes (PT). This practice should be a periodic activity and in accordance with the international standards. In the paper the results of the international ILC conducted by the Laboratory of Electrical Measurements (LEM) of the Faculty of Engineering and Information Technologies at the Ss. Cyril and Methodius University in Skopje, R. Macedonia (pilot laboratory), and the High Tech Test shpk – Tirana, R. Albania (HTT), both accredited laboratories, will be presented. The ILC accomplished in the period March–April 2017 was conducted through cali-bration of 6½ digital multimeter Keysight 34401A for various electrical quantities. In the paper, the detailed meas-urement procedure followed by the two laboratories as well as the evaluation and acceptance criteria will be given. The results of the ILC will be presented and discussed. The ILC gives a significant contribution the quality and con-fidence assurance in electrical quantities measurements at national and regional/international level.

Finding ways to decrease the measurement uncertainty for participation in interlaboratory comparisons of measurement of mass

As the title implies the article analyzes the factors that affect the result of evaluation of measurement uncertainty. It is specially noted need for participation of calibration laboratories in interlaboratory comparisons to obtain objective evidence of competence. The basic formulas for the estimation of measurement uncertainty in the calibration of measurement standards of mass are examined. The main activities undertaken of calibration laboratory for minimizing measurement uncertainty are described. These events have provided to the positive results in interlaboratory comparisons and provide traceability of calibration results to the national measurement standard of mass unit.

Correlation of coagulation indicators with inflammatory markers in the acute pancreatitis patients

In the last few years much progress has been made in raising the awareness of laboratory medicine professionals about the effectiveness of quality indicators (QIs) in monitoring, and improving upon, performances in the extra-analytical phases of the Total Testing Process (TTP).An effective system for management of QIs includes the implementation of an internal assessment system and participation in inter-laboratory comparison. A well-designed internal assessment system allows the identification of critical activities and their systematic monitoring. Active participation in inter-laboratory comparison provides information on the performance level of one laboratory with respect to that of other participating laboratories.In order to guarantee the use of appropriate QIs and facilitate their implementation, many laboratories have adopted the Model of Quality Indicators (MQI) proposed by Working Group “Laboratory Errors and Patient Safety” (WG-LEPS) of IFCC, since 2008, which is the result of international consensus and continuous experimentation, and updating to meet new, constantly emerging needs.Data from participating laboratories are collected monthly and reports describing the statistical results and evaluating laboratory data, utilizing the Six Sigma metric, issued regularly.Although the results demonstrate that the processes need to be improved upon, overall the comparison with data collected in 2014 shows a general stability of quality levels and that an improvement has been achieved over time for some activities. The continuous monitoring of QI data allows identification all possible improvements, thus highlighting the value of participation in the inter-laboratory program proposed by WG-LEPS.The active participation of numerous laboratories will guarantee an ever more significant State-of-the-Art, promote the reduction of errors and improve quality of the TTP, thus guaranteeing patient safety.

Measurement Error Models for Interlaboratory Comparison Measurement Data

Test laboratories with International Organization for Standardization/International Electrotechnical Commission 17025:2005 accreditation are obliged to calculate measurement uncertainty and declare the calculated value. Furthermore, they have to ensure the quality of the test results, and their participation in interlaboratory comparisons is mandatory for the accreditation. To this end, a standard procedure is available, and the laboratory's performance is also assessed by comparing its results with the reference value. While several studies consider the problem of analyzing interlaboratory comparison data, the problem still remains of how to include all the measurements (containing uncertainties and outliers) and all the dispersion effects arising during the test activity, in the analysis. This paper aims to improve the analysis of interlaboratory comparison data by focusing on an error measurement model, which considers the declared measured values and the corresponding uncertainties, and by also accounting for other dispersion effects involved in the interlaboratory activity. The problems of the small sample size and the presence of outliers are taken into account through the calculation of confidence intervals, by also evaluating the contribution of the variances estimated for the uncertainties, namely, by the signal-to-noise and reliability ratios. Moreover, the laboratory's performance is assessed by discriminating for the presence of outliers related to the reference value and/or to the uncertainty. The results are satisfactory in view of the issues addressed in this study, especially if we consider the specific kind of data. Copyright © 2016 John Wiley & Sons, Ltd.

The “PTB Ex Proficiency Testing Scheme” - Interlaboratory Comparisons in the Field of Explosion Protection

The requirement of participation in interlaboratory comparisons was not sufficiently fulfilled by laboratories in the field of explosion protection (Ex-testing laboratories) due to a lack of proficiency testing programs. The reasons were the extensive effort, the complexity of the relevant measurands- and characteristics of interest and difficulties with the selection of appropriate test samples.The present paper introduces the PTB Ex Proficiency Testing Scheme as the first comprehensive proficiency testing program in explosive protection. Furthermore, a detailed look into the program “Explosion Pressure” is presented with a discussion about the reasons for differences in the results of the participants. It is shown that the scheme can improve the performance of the participated Ex-testing laboratories which generates additional confidence for the whole community related to the topic explosion protection..