Accreditation and Quality Assurance最新文献

ISO Standards provide a minimal benchmark for organisations to achieve accreditation or certification and maintain compliance to the core elements of the standard. These standards assist organisations in establishing and maintaining a quality management system. Business Excellence models are integrated collections of proven activities for how an organisation should operate to pursue excellence or world-class performance and sustainability. The focus is on the customers and internal processes to meet customer expectations. The pursuit of ISO compliance and business excellence are interrelated, synergistic and will lead to common approaches for progress and sustainability if well managed. Embracing quality assurance systems, tools of organisational excellence and benchmarking against the best international standards and practices are essential for businesses operating in a global community. The Royal College of Pathologists of Australasia Quality Assurance Programs Pty Ltd has long been a compliance-driven organisation, but more recently embraced the pursuit of business excellence by adopting the Australian Business Excellence Framework. These two approaches to quality management and continual improvement are compared and the value of incorporating both approaches is explored.

As the only ISO/IEC 17043:2010-accredited food PT provider in the Philippines since 2013, the Department of Science and Technology-Food and Nutrition Research Institute successfully organized a PT Round on corn-based snack food for nutrition labeling parameters. The PT Round aimed at evaluating the performance of chemical laboratories in the Asia-Pacific area on the analysis of proximates (moisture, fat, protein and ash), total dietary fiber (TDF), saturated fatty acids and minerals (iron, calcium, sodium, potassium and zinc) in corn-based snack food through an interlaboratory comparison. A sufficiently homogeneous corn-based snack food test item was distributed to 67 registered laboratories. Results were evaluated using appropriate statistical procedures based on ISO 13528:2015. The mass fractions such as moisture, fat, protein, saturated fatty acids, calcium, sodium, potassium and zinc in corn-based snack food, which have x_pt with negligible uncertainties, i.e., u(x_pt) ≤ 0.3σ_pt, were issued with z scores, while other measurands with wide variability in the results, i.e., u(x_pt) > 0.3σ_pt, were issued with z′ scores. The x_pt (in % for proximates, TDF and saturated fatty acids, and 10^–5 g/g for minerals) and the percentage of laboratories that obtained “Satisfactory” performance (│z or z′ score│ ≤ 2) were: moisture (2.95, 88 %), fat (15.75, 91 %), protein (9.75, 69 %), ash (1.61, 64 %), TDF (5.04, 54 %), saturated fatty acid (5.90, 78 %), iron (2.93, 69 %), calcium (161, 74 %), sodium (139, 82 %), potassium (170, 77 %) and zinc (2.68, 85 %). This PT Round allowed to assess laboratories’ performances on the analysis of nutrition labeling parameters in corn-based snack food and improvement on performance by conducting investigative and corrective actions for those participants with “Warning” and “Action” signals.

Dominik Pražák recently published in this journal a thoughtful discussion of the implications of a shortage of Latin letters for use in the SI. This is a short reply, intended to develop the opinions in that article.

Proficiency testing providers, accreditation bodies and testing laboratories should be aware that a laboratory participating in a proficiency testing round might have reported a biased result despite a satisfactory performance indicated by an assessment using uniquely the z score. A complementary performance evaluation, based on the ζ score and the assessment of the measurement uncertainty, is therefore highly recommended. This work presents an intuitive graphical tool (the Naji2 plot) that combines z and ζ scores together with the reported measurement uncertainties. This tool allows a comprehensive assessment of the laboratory performance and enables to identify the need for corrective actions. The concerned laboratory should then perform a root cause analysis and investigate their bias and/or their measurement uncertainty evaluation.

Objectives

Implementation of standard laboratory practices towards accurate antimicrobial susceptibility testing (AST) is challenging in resource-constrained settings. Efforts to improve AST are required to address knowledge and practice gaps in such settings. In this study, we aimed to address these gaps through external quality assurance surveys and mentoring of laboratories in Pakistan.

Methods

This prospective study (May 2017–September 2019) included 10 consenting laboratories. External quality assessment (EQA) was conducted quarterly and performance scored. Each EQA cycle was followed by an on-site technical visit during which AST methodology, quality procedures and laboratory safety were evaluated using a questionnaire developed for this study. Cumulative scores of performance in the EQA and in the technical evaluation were designated “Composite Laboratory Performance Score; CLPS”. During on-site visits, feedback provided was to each participating laboratory towards addressing gaps identified.

Results

Over the course of the study, our data show significant improvement in CLPS amongst the laboratories included. While improvement in the CLPS scores varied between laboratories, a linear regression model showed improvement within the cohort from 21.37 (May 2017) to 91.5 (September 2019); a significant overall increase of 70.13 points (p = 0.001).

Conclusion

Interventions to improve AMR surveillance include quality assured reporting of antimicrobial resistance. Our data show that in resource-limited settings EQA surveys and on-site evaluations followed by guidance contribute towards such improvement. We propose that this model would be a useful tool for laboratory strengthening in such settings.

Monitoring pesticide residues is a key item in the field of food safety. Tea matrices represent a challenge in pesticide analysis due to the high content of coextracts. An interlaboratory comparison was organized to assess the performance of 73 laboratories, from 28 regions in China, on the quantification of five pesticide residues in tea matrix reference material in order to ensure the accuracy, reliability and comparability of monitored pesticide residues in foods. The tea matrix reference material spiked with pesticides was prepared according to ISO 17034. Briefly, blank green tea was spiked with bifenthrin, permethrin, fenpropathrin, buprofezin and imidacloprid, smashed, sieved, homogenized and bottled. It was assessed to be sufficiently homogeneous and stable. Participant laboratories were requested to submit quantification results with detailed analytical protocols. Assigned values were obtained from consensus values by robust analysis, and the results were assessed using z scores. The robust standard deviations for five pesticides were lower than the expected standard deviations in our interlaboratory comparison. In total, 93.8 % (255/272) of the results were acceptable (|z|≤ 2.0) and 82.2 % (60/73) of participant laboratories had satisfactory performance in pesticide residues quantification. Analytical protocols of extraction, cleanup and quantification methods were reviewed to assess their impacts on the results. Overall, a tea matrix reference material was successfully prepared for an interlaboratory comparison, and the results indicate that most of domestic laboratories have acceptable capability in pesticides quantification, while a few of them need to further optimize their protocols to improve performance.

Natural gas is the most widely used energy source among other gases. For this reason, measuring the gross calorific value with very high precision is of great importance for users and sellers. With the reference calorimeter designed in this study, it was aimed to obtain the calorific value “H_m” of the methane gas which is the principal component of the natural gas and has the EN ISO 6976:2016 standard. The measurements made with the designed and manufactured reference calorimeter were evaluated. The reference calorimeter can measure temperature, mass, power, amount of wastewater absorbed, type and amount of waste gas with the highest precision that TUBITAK-NMI (The Scientific and Technological Research Council of Turkey)-(National Metrology Institute) can measure. Measurements made with the designed calorimeter were insulated so that there is no heat exchange from the external environment, while the gas flow rate and temperature provided by using stable temperature sources are controlled. Certified calibration instruments were used in all measurements. The experiments were carried out at a temperature of 298.16 K. The methane gas with 99.995 % purity was used as the reference gas and as a result of the measurements; experimental data were obtained with errors ranging from 0.5 % / 0.1 %. Analyses from experimental data have shown that the greatest error in gross calorific value “(H_m)_G” is due to temperature and mass measurements. The mean gross calorific value obtained using eight measurements is 55460.60 kJ kg⁻¹ or 889.03343 kJ mol⁻¹ within a relative expanded uncertainty of 0.2 % (k = 2).

The production of a simulated urine sample is necessary for external quality assessment schemes in clinical testing. This study aimed to optimize the formulation of a simulated urine sample containing patient urine bacterial Enterococcus faecalis via response surface methodology based on central composite design. The results of a Plackett–Burman design experiment showed that three factors including sodium thioglycolate and peptone concentration and pH value significantly effected to concentration of E. faecalis. Notably, an initial concentration of 1.51 mg/mL of sodium thioglycolate and 3.63 mg/mL of peptone at a pH value of 8.06 of culture medium has been found to maximize the E. faecalis concentration (7.05 log (CFU/mL)). This optimal condition could be applied for production of a simulated urine sample containing E. faecalis.

This paper introduces the implementation of ISO Guide 34 and ISO 17034 in the Mainland of P R China, especially from the accreditation viewpoint. The comparisons are made regarding different aspects in accreditation, including the accreditation number, the growth (rate) as well as the findings identified during onsite assessments between reference material producers and testing laboratories. The distribution of the non-conformities is also discussed to show the impact of the changed structure from ISO Guide 34 to ISO 17034, with the presentation of highlighted typical non-conformities against ISO 17034.

The importance of quality in analytical chemistry stimulates the development of different tools to assure the reliability of analytical results. Among different tools, proficiency testing (PT) stands out because it can be used to evaluate bias, check uncertainty, train analysts, or certify if a laboratory can execute a method adequately and provide correct results. There is a growing demand for traceable and reliable results in analytical chemistry, which can be illustrated with the growth of ISO/IEC 17025 accreditation and the importance of PT in this context. This has led to an increase in developments and publications about PT programs. This paper reports a detailed review considering the best practices to develop PT for chemical analysis, focusing on food and environmental matrices. An evaluation of the trends and the statistical strategies in its development in the last two years was performed to guide new developments of this tool that is increasingly necessary for laboratories.