Establishing an Iranian medical laboratory standard based on ISO 15189

To strengthen clinical laboratories’ capabilities, the Reference Health Laboratory (RHL) of the Ministry of Health decided to compile a national professional laboratory standard to be followed by all medical laboratories in the country. Providing a national laboratory standard, as approved criteria for competency assessment, is also essential for establishment of a national accreditation system for medical laboratories. ISO 15189 addresses different processes and activities in a medical laboratory, but considering the local situation and limitations in the country it was not feasible to implement all the requirements of ISO 15189 at once in laboratories in different sectors and in different provinces of the country. For this reason, the RHL decided to define and publish the national standard, as minimum quality requirements that could be mandatory for all clinical laboratories throughout the country. After conducting a countrywide situation analysis, a national standard was composed by RHL expert committees and officially announced in September 2007. The main reference of this standard was ISO 15189:2007, although some important technical details were added to it from other credible references, such as WHO documents and CLSI guidelines. In this study, the Iranian national standard is compared to ISO 15189:2007 in terms of format and content in order to show how an international standard was localized for compiling a national standard.     

Estimation of measurement uncertainty in food microbiology: The ISO approach

Given the current interest in measurement uncertainty (MU) in food microbiology, in particular for laboratory accreditation purposes, and the need to have harmonized reference documents specifically in that area at the international level, ISO is conducting works to meet this need. An ISO Technical Specification (ISO/TS 19036) is being prepared on MU estimation for quantitative determinations. A global approach has been chosen, based on the reproducibility standard deviation of the final result of the measurement process. Three possibilities are envisaged for the estimation of the reproducibility standard deviation, in a decreasing order of preference: The intra-laboratory standard deviation, the inter-laboratory standard deviation derived from method validation, and the inter-laboratory standard deviation derived from proficiency testing.The uncertainty of qualitative determinations is still under investigation, and will be covered by a separate ISO publication. Presented at AOAC Europe/Eurachem Symposium March 2005, Brussels, Belgium     

Blood banking quality: minimum requirements for TQM

In 1995, the Council of Europe published a guide with recommendations providing transfusion services with a set of guidelines and principles relating to the preparation, use and quality assurance of blood components. As a blood transfusion service is at the same time a supplier of blood products and a test laboratory the quality management system must include good medical practice, good manufacturing practice and good laboratory service, all of which are closely linked. We made a critical evaluation of the content of the guide and analysed requirements and recommendations in comparison with quality management systems applied by the concerned partners. As a major critic we observed that the guide does not take into account any quality system of the in vitro diagnostic (IVD) supplier and/or distributor. With the addition of some items outlined in ISO 25 and ISO 9000, the Council of Europe document can be improved so that it complies with internationally accepted quality management standard recommendations.     

Practical experience of simultaneous accreditation and certification acquired in RIVM's official medicines control laboratories

 This article presents an overview of the practical experience acquired in two governmental medicines control laboratories in the Netherlands which combine the application of EN 45001 and ISO 9002 standards in the regulatory field of quality and risk assessment, and quality control of medicines and medical devices. This practical experience also includes simultaneous accreditation and certification. The EN 45001 standard was applied to laboratory testing activities and the ISO 9002 standard to non-laboratory file assessment activities as these activities are not covered by the scope of EN 45001. It appears that a combined application of these standards is practicable because they complement each other well. EN 45001 strongly emphasises technical competence. ISO 9002, on the contrary, emphasises more strongly the efficiency of the management processes and customer requirements. Received: 1 October 1998 · Accepted: 21 December 1998     

Sterilization validation for medical compresses at IRASM multipurpose irradiation facility

In Romania, IRASM Radiation Processing Center is the unique supplier of radiation sterilization services—industrial scale (ISO 9001:2000 and ISO 13485:2003 certified). Its Laboratory of Microbiological Testing is the sole third party competent laboratory (GLPractice License, ISO 17025 certification in progress) for pharmaceutics and medical devices as well.We here refer to medical compresses as a distinct category of sterile products, made from different kind of hydrophilic materials (cotton, non-woven, polyurethane foam) with or without an impregnated ointment base (paraffin, plant extracts). These products are included in the class of medical devices, but for the sterilization validation, from microbiological point of view, there are important differences in testing method compared to the common medical devices (syringes, catheters, etc).In this paper, we present some results and practical solutions chosen to perform a sterilization validation, compliant with ISO 11137: 2006.     

Metrological Assurance of Biodevices: The New Method of Calibration of Biochemical Analyzers

Abstract

Medical diagnostics and therapy use an extensive amount of electronics, optoelectronics, and laser devices. For their reliable functioning, calibration is unavoidable. Biochemical analyzers, which work on principles of absorptional spectrophotometry, became most widely present in medical biochemical laboratories. Construction of these devices is such, that in most cases, it does not allow calibration by usual methods, using neutral density (ND) filters as standards. For this reason, it was necessary to create a solution that could be used as a mean of comparison or even as a standard solution for methods of calibration of biochemical analyzers. In this article, the metrological characterization of solutions that are developed is presented, and the measuring uncertainty (ISO 1993) of methods used for calibration is estimated.

The method that is developed provides metrological traceability to the primary spectrophotometric standard. With this method, metrological assurance in the field of the spectrophotometry in medical laboratories is completed.     

Enumeration of total yeasts and molds in foods by the SimPlate Yeast and Mold-Color Indicator method and conventional culture methods: collaborative study

The relative effectiveness of the SimPlate Yeast and Mold-Color Indicator method (Y&M-CI) was compared to the U.S. Food and Drug Administration's (FDA) Bacteriological Analytical Manual (BAM) method and the proposed International Organization for Standardization (ISO) method, ISO/CD 21527, for enumerating yeasts and molds in foods. Test portions were prepared and incubated according to the conditions stated in both the BAM and ISO methods. Six food types were analyzed: frozen corn dogs, nut meats, frozen fruits, cake mix, cereal, and fresh cheese. Nut meats, frozen fruits, and fresh cheese were naturally contaminated. All other foods were artificially contaminated with either a yeast or mold. Seventeen laboratories throughout North America and Europe participated in the study. Three method comparisons were conducted. In general, there was <0.3 mean log count difference in recovery between the SimPlate method and the 2 corresponding reference methods. Moreover, mean log counts between the 2 reference methods were also very similar. The repeatability (Sr) and reproducibility (SR) standard deviations were comparable between the 3 method comparisons. These results indicate that the BAM method and the SimPlate method are equivalent for enumerating yeast and mold populations in foods. Similarly, the SimPlate method is comparable to the proposed ISO method when test portions are prepared and incubated as defined in the proposed ISO method.     

Implementation of ISO 9001 in a medical testing laboratory

 The Department of Clinical Chemistry and Molecular Genetics, within the Institute of Clinical Pathology and Medical Research at Westmead Hospital, is a medical testing laboratory operating within the public sector health system of New South Wales, Australia. It provides acute-care pathology services to Westmead Hospital (a 900-bed tertiary referral university teaching hospital) as well as to three district hospitals and three rural hospitals. In addition to these core clinical chemistry services, it offers approximately 150 specialised biochemistry, pharmacology, toxicology, trace metal and molecular genetics assays as a reference laboratory service. In 1993, the Department became Australia's first medical testing laboratory to be registered to ISO 9001-1987/AS3901-1987. In 1995, this certification was extended to AS/NZS ISO 9001-1994. We are currently preparing for further accreditation to ISO/IEC Guide 25-1990, with additional supplementary requirements for medical testing. This paper describes the Quality System that the Department developed and which has been successfully maintained and extended since original certification. Important features of the Quality System are: 1. Primary design of the Quality System to meet medical and customer needs, with subsequent addition of required ISO elements. 2. Use of national Quality Award criteria to identify key business processes. 3. Development of integrated technical non-conformance, customer complaint, staff suggestion, and quality system corrective action procedures. 4. Implementation without external resources. Our conclusions are that ISO 9000 Quality Systems can be applied to medical testing laboratories, and can be implemented with minimum resource costs. Improvements in technical and service quality and business performance have resulted from this process. However, implementation of ISO 9000 at the level of individual Departments is not ideal. Greater improvements are possible when this process is undertaken at the level of the entire organisation. Received: 9 September 1996 Accepted: 5 October 1996     

The Japanese traceability system and the role of uncertainty evaluation in measurement

 The new traceability system of measurement standards based on the Japanese Measurement Law has been established since November 1993. Some reference materials such as metal standard solutions, pH standard solutions and standard gas mixtures are included in the system together with relevant physical quantities. In this system, primary measurement standard instruments or primary reference materials are designated by the regulation for each quantity. For the practical dissemination of each quantity, accreditation of calibration bodies is recognized by the steering committee under the supervision of the government. In the course of assessment of a candidate calibration body, the concepts of ISO/IEC Guide 25 and ISO/IEC Guide 58 are effectively introduced. For the estimation of reliability, the concept of how to introduce the statistical approach is effectively considered. The method of uncertainty evaluation described in the ISO document entitled "Guide to the expression of uncertainty in measurement" is adopted.     

Comments on the Japanese study of the radiation resistance of the bioburden of medical devices

The findings obtained in an extensive study of the radiation resistance of microbes forming the bioburden of a number of medical devices has been carried out by Takehisa et al. and reported in this number of this Journal. The following paper reviews the expected behaviour of the reported populations under the conditions specified in ISO Standard 11137 Method 1, which is widely used in the determination of the radiation sterilization dose required for sterilization of medical devices. The populations reported for “dry” devices contain a higher proportion of more radiation resistant microbes than that found in the standard distribution of resistance (SDR) that is used for setting the sterilization dose in Method 1. A possible alternative dose setting method for more resistant microbial populations is introduced and discussed.     

Enumeration of total aerobic microorganisms in foods by SimPlate Total Plate Count-Color Indicator methods and conventional culture methods: collaborative study

The relative efficacy of the SimPlate Total Plate Count-Color Indicator (TPC-CI) method (SimPlate 35 degrees C) was compared with the AOAC Official Method 966.23 (AOAC 35 degrees C) for enumeration of total aerobic microorganisms in foods. The SimPlate TPC-CI method, incubated at 30 degrees C (SimPlate 30 degrees C), was also compared with the International Organization for Standardization (ISO) 4833 method (ISO 30 degrees C). Six food types were analyzed: ground black pepper, flour, nut meats, frozen hamburger patties, frozen fruits, and fresh vegetables. All foods tested were naturally contaminated. Nineteen laboratories throughout North America and Europe participated in the study. Three method comparisons were conducted. In general, there was <0.3 mean log count difference in recovery among the SimPlate methods and their corresponding reference methods. Mean log counts between the 2 reference methods were also very similar. Repeatability (Sr) and reproducibility (SR) standard deviations were similar among the 3 method comparisons. The SimPlate method (35 degrees C) and the AOAC method were comparable for enumerating total aerobic microorganisms in foods. Similarly, the SimPlate method (30 degrees C) was comparable to the ISO method when samples were prepared and incubated according to the ISO method.     

Can the usual validation standard series for quantitative methods,ISO 5725, be also applied for qualitative methods?

Repeatability standard deviation, laboratory standard deviation, and reproducibility standard deviation for quantitative methods according to ISO 5725 series were recently proposed to estimate the precision of qualitative measurements, giving a presence/absence response. In this paper, it is shown that for qualitative methods, the reproducibility standard deviation across laboratories does not reflect the performance of the method as suggested. It is demonstrated that the benefit of the respective laboratory standard deviation is very limited. Alternative performance measures are introduced which are based on another approach also directly linked to ISO 5725. Thereby, meaningful information about the precision of qualitative test methods can be achieved.     

Effects of digital processing on repeatability assessment of a multiple reaction monitoring liquid chromatography–tandem mass spectrometry system by ISO 11843-7

ISO 11843 part 7 (ISO 11843-7) can provide a standard deviation (SD) of area measurements of a target peak through the stochastic behaviors of instrumental noises. The purpose of this study is to demonstrate that ISO 11843-7 can be applied to assess repeatability in an isocratic liquid chromatography–tandem mass spectrometry (LC–MS/MS) system without repetitive measurements. The relative standard deviation (RSD) of the peak area of ergosterol picolinyl ester, which was used as an example, on a multiple reaction monitoring (MRM) chromatogram was determined by ISO 11843-7. The RSD by ISO 11843-7 (N = 1) was within a 95% confidence band of the RSD by repetitive measurements (N = 6). Moreover, the effects of digital smoothing, such as moving average, were also examined on the repeatability assessment in LC–MS/MS by ISO 11843-7. From the results of the comparisons of the RSDs obtained by ISO 11843-7 and the repetitive measurements, it was shown that suitable RSDs of the peak area were obtained from the smoothed MRM chromatograms by the moving average for narrow data point windows (e.g., one-sixth of the peak width). In conclusion, the utility of repeatability assessment based on ISO 11843-7 has been expanded for the validation of an LC–MS/MS system.     

Implementation of a quality management system in meteorological practice in Serbia

An optional approach in the meteorological service Quality Management System (QMS) based on the case study of the Republic Hydrometeorological Service (MHS) of Serbia is presented and discussed in this paper. The idea is to use the ISO/IEC 17025 standard as a base for its QMS development. Main reasons for such a decision and the elements of the implemented solution are presented and discussed. Meteorological testing processes of the MHS of Serbia and relevant ISO/IEC 17025 scope of accreditation are presented. After establishing competencies in meteorological, environmental, and hydrological testing, the MHS of Serbia will develop an integrative ISO 9001 QMS. The Serbian case study could be taken into consideration as one of the options related to the future World Meteorological Organization Quality Management Framework.     

Do multi-use cellulosic textiles provide safe protection against the contamination of sterilized items?

The aim of this study was to determine whether multiple use cellulosic medical textiles (cotton blends, Tencel^®) could provide protection against contamination after sterilization, regardless of the barrier system of only qualified materials, as per EN 868-2, used in the process. New methods for testing permeability and durability of the microbial barrier cellulosic textiles were developed. The most resistant endospores of two apathogenic bacteria of the Bacilllus genus (Geobacillus stearothermophilus and Bacillus atrophaeus) were used. Testing was conducted after 1, 10, 20, 30 and 50 washing and sterilization cycles under real hospital conditions of the University Hospital Centre Zagreb. The retention period of the microbial barrier of the diagonally packaged packages (one layer; EN ISO 11607-1:2009) after sterilization was tested after the time period of 1, 2 and 3 months of storage under controlled conditions. Bacterial permeability occurred in cellulosic medical textiles when they were contaminated with an extremely high quantity of aerobe bacterial spores. During the testing of microbial barrier durability, the package remained uncontaminated after 1, 2 and 3 months of storage. Medical cellulose textiles used under real hospital conditions functioned properly as a microbial barrier system after 50 cycles of washing and sterilization and 3 months of storage, as the sterilized content was not contaminated at all; they could be used as a microbe barrier system for packing in sterilization, regardless of the fact that they did not meet the standard EN 868-02:2009 Packaging materials for terminally sterilized medical devices. Part 2: sterilization wrap—requirements and test methods or the International standard, for example EN ISO 11607-1:2009 Packaging for terminally sterilized medical devices, part 1: requirements for materials, sterile barrier systems and packaging systems.     

Accrediting PT/EQA providers to ISO/IEC 17043

After many years and having several different attempts for the accreditation of proficiency testing provider (PT provider), there is finally one stand-alone standard defining the requirements for the competence of PT providers and therefore an internationally harmonised basis for the accreditation of proficiency test providers. Since February 2010, the ISO/IEC 17043:2010 has replaced ISO/IEC Guide 43:1997 and ILAC G 13:2007. The philosophy of the standard about subcontracting work is different to this of the standards mostly used for accreditation like ISO/IEC 17025:2005 or ISO/IEC 17020:2004, etc. Besides the planning of the proficiency tests (PT), the performance evaluation and the authorisation of the PT reports the ISO/IEC 17043:2010 allows subcontracting for the rest of the work when providing PTs. This is a challenge for the assessors to judge about the competence of a PT provider. In numerous paragraphs, the standard sets very detailed requirements. Nevertheless, there is room for interpretation. For these cases, for example, contracts for subcontractors, procedure for the advisory board, minimum requirements for PT certificates, etc., some proposals are given to enable harmonised approach for the assessment of PT providers.     

Comparison of permeation resistance of protective gloves to organic solvents with ISO, ASTM and EN standard methods

In this study, the permeation resistance of nitrile and neoprene gloves to benzene and 1,2-dichloroethane was investigated using two permeation cells according to the ISO 6529, ASTM F739, and EN 374-3 standard test methods. The permeability coefficients were found to significantly increase with the flow rate of the collection medium. The appropriate flow rate of nitrogen collection should be higher than 75 and 150 mL/min for the ISO 6529 and ASTM F739 cells, respectively. For an open-loop system, the permeability coefficient of the ISO 6529 cell was obviously greater than that of the ASTM F739 cell, and the difference between these two cells was statistically significant. On the other hand, the breakthrough time was about 20–30 min for either the ISO 6529 or ASTM F739 cell at different flow rates of nitrogen collection. Fick's diffusion coefficient and solubility of permeant in the polymer glove can be specified as alternative test results for standard methods.     

水中氟化物国际标准检验方法的验证及其比较

介绍水中氟化物国际标准检验方法的验证结果,其中包括了干扰实验、标准曲线、准确度、精密度、检出限等.并将本方法测定结果与国标同类方法进行了比较.结果表明,该方法抗干扰性好,测量精度高,其标准曲线范围宽,点数设计合理,优于国标中的同类方法.应加以采纳和推广.     

Comparison of international standards concerning the capability of detection for analytical methods

The international standard ISO 11843 specifies the experimental conditions for the estimation of critical values of analytical methods referring to the capability of detection. The present paper aimed at a formal comparison of the ISO 11843 standard with the German standard DIN 32645 and the Commission Decision 2002/657/EC of the EU. In this context the particular scope of each standard is discussed based on a numerical example given in the DIN standard. For practitioners a better understanding of the different guidelines based on the same basics, i.e. the statistical theory of hypothesis testing and the probabilities of false positives α and false negatives β, is to be achieved.     

Determination of dissolved bromate in drinking water by ion chromatography and post column reaction: interlaboratory study

A collaborative study, International Evaluation Measurement Programme-25a, was conducted in accordance with international protocols to determine the performance characteristics of an analytical method for the determination of dissolved bromate in drinking water. The method should fulfill the analytical requirements of Council Directive 98/83/EC (referred to in this work as the Drinking Water Directive; DWD). The new draft standard method under investigation is based on ion chromatography followed by post-column reaction and UV detection. The collaborating laboratories used the Draft International Organization for Standardization (ISO)/Draft International Standard (DIS) 11206 document. The existing standard method (ISO 15061:2001) is based on ion chromatography using suppressed conductivity detection, in which a preconcentration step may be required for the determination of bromate concentrations as low as 3 to 5 microg/L. The new method includes a dilution step that reduces the matrix effects, thus allowing the determination of bromate concentrations down to 0.5 microg/L. Furthermore, the method aims to minimize any potential interference of chlorite ions. The collaborative study investigated different types of drinking water, such as soft, hard, and mineral water. Other types of water, such as raw water (untreated), swimming pool water, a blank (named river water), and a bromate standard solution, were included as test samples. All test matrixes except the swimming pool water were spiked with high-purity potassium bromate to obtain bromate concentrations ranging from 1.67 to 10.0 microg/L. Swimming pool water was not spiked, as this water was incurred with bromate. Test samples were dispatched to 17 laboratories from nine different countries. Sixteen participants reported results. The repeatability RSD (RSD(r)) ranged from 1.2 to 4.1%, while the reproducibility RSD (RSDR) ranged from 2.3 to 5.9%. These precision characteristics compare favorably with those of ISO 15601. A thorough comparison of the performance characteristics is presented in this report. All method performance characteristics obtained in the frame of this collaborative study indicate that the draft ISO/DIS 11206 standard method meets the requirements set down by the DWD. It can, therefore, be considered to fit its intended analytical purpose.