Interlaboratory Quality Control Research Articles

International circumpolar surveillance: update on the interlaboratory quality control program for Streptococcus pneumoniae, 2009 to 2020.

Arctic populations experience several social and physical challenges that lead to the increased spread and incidence of invasive diseases. The International Circumpolar Surveillance (ICS) program was developed to monitor five invasive bacterial diseases in Arctic countries and territories. Each ICS organism has a corresponding interlaboratory quality control (QC) program for laboratory-based typing, to ensure the technical precision and accuracy of reference testing services for these regions, and identify and correct potential problems. Here, we describe the results of the ICS Streptococcus pneumoniae QC program, from 2009 to 2020. Excellent overall concordance was achieved for serotype and antimicrobial susceptibility testing results across six laboratories. Ongoing participation in these QC programs ensures the continuation of quality surveillance systems within Arctic populations that experience health disparities.

Comparison of the sigma metrics using the total error allowable algorithm with variation of bias source

Sigma Metrics, as a quality indicator, have been widely applied in clinical laboratories to assess the performance of analytical methods. Described in the document Clinical and Laboratory Standards Institute (CLSI) EP15- A3, the use of target values can be sourced from certified reference standards, survey materials from the Proficiency Testing (PT)/External Quality Assessment (EQA), materials used in inter-laboratory quality control programs and internal quality control materials with predetermined targets. This research aims to determine whether there is a difference in the sigma metrics between the bias derived from the manufacturer's target value and those from the peer group source in the External Quality Assurance Services (EQAS) program. The research methodology employed is descriptive comparative analysis, utilizing the results of material inspection data for 15 internal quality control parameters of Clinical Chemistry over a span of 2 years at the Pramita Laboratory in Bandung. The calculation of the sigma metrics commences with computing the coefficient of variation (CV), and the appropriate Total Error aalowable (Tea) sources for each parameter are determined beforehand using the TEa algorithm. The research findings indicate a difference between the sigma metrics derived from the manufacturer's target value and those from the EQAS-peer group target value, accounting for 33% or 10 parameters out of the total parameters with 2 levels of inspection are calculated on the sigma scale. However, in 67% or 20 parameters out of the total parameters, no such difference is observed. Bias associated with the target value from the manufacturer and the EQAS peer group shows no significant difference, suggesting that the laboratory can utilize pre-existing target values confidently.

Quality assurance of SARS-CoV-2 testing laboratories during the pandemic period in India – An experience from a designated provider laboratory

PurposeIndian Council of Medical Research (ICMR) initiated an Inter-Laboratory Quality Control testing (ILQC) program for Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) testing. Under this program, SARS-CoV-2 testing laboratories across the country submit specimens to the assigned State Quality Control (SQCs) laboratories for ILQC testing. This study aimed to investigate the performance of public and private SARS-CoV-2 testing laboratories in Delhi and highlights the country’s effort in ramping up testing facility with close monitoring of the quality of Covid-19 testing results. MethodsIn the present study, two-years of SARS-CoV-2 testing data is included. During July 2020 through February 2022, a total of 1791 anonymised specimens were received from 56 public and private laboratories. These specimens were processed by reverse transcriptase – polymerase chain reaction (RT-PCR) tests as per National Institute of Virology (NIV) protocol and the results were uploaded on the ICMR quality control/quality assurance (QC/QA) portal without directly conveying the results to respective participating laboratories. This portal generated a final report stating concordance and intimate results to individual laboratories. ResultsAmong the 1791 specimens, 25 were rejected and the remaining 1766 were tested. Among these specimens 1691 (95.75%) revealed concordance, and 75 (4.24%) were discordant. A total of 29 laboratories had 100% concordance, 21 laboratories had over 90% concordance and six laboratories had over 80% concordance. ConclusionsThe study demonstrates that the establishment of an inter-laboratory comparison program for SARS-CoV-2 testing helped in monitoring quality of SARS-CoV-2 testing in the country.

Ten-year results of an international external quality control programme for measurement of anti-tuberculosis drug concentrations.

Participation in an external (interlaboratory) quality control (QC) programme is an essential part of quality assurance as it provides laboratories with valuable insights into their analytical performance. We describe the 10 year results of an international QC programme for the measurement of anti-tuberculosis (TB) drugs. Each year, two rounds were organized in which serum (or plasma) samples, spiked with known concentrations of anti-TB drugs, were provided to participating laboratories for analysis. Reported measurements within 80%-120% of weighed-in concentrations were considered accurate. Mixed model linear regression was performed to assess the effect of the measured drug, concentration level, analytical technique and performing laboratory on the absolute inaccuracy. By 2022, 31 laboratories had participated in the QC programme and 13 anti-TB drugs and metabolites were included. In total 1407 measurements were reported. First-line TB drugs (isoniazid, rifampicin, pyrazinamide and ethambutol) represented 58% of all measurements. Overall, 83.2% of 1407 measurements were accurate, and the median absolute inaccuracy was 7.3% (IQR, 3.3%-15.1%). The absolute inaccuracy was related to the measured anti-TB drug and to the performing laboratory, but not to the concentration level or to the analytical technique used. The median absolute inaccuracies of rifampicin and isoniazid were relatively high (10.2% and 10.9%, respectively). The 10 year results of this external QC programme illustrate the need for continuous external QC for the measurement of anti-TB drugs for research and patient care purposes, because one in six measurements was inaccurate. Participation in the programme alerts laboratories to previously undetected analytical problems.

B-356 Advancements in Commercial Viability of a Blood Test for the Early Detection of Breast Cancer

Abstract Background Mammography is the current diagnostic standard for breast cancer screening and monitoring. However, accessibility challenges, accuracy issues and patient discomfort all contribute to reduced patient compliance and utilization, resulting in a need for more effective diagnostic tools. A blood test to detect early-stage breast cancer is sought to increase the screening detection rate, provide more accurate monitoring tools, and improve outcomes for patients. We have previously reported a series of lipidomic studies and derived a lipid signature from plasma enriched extracellular vesicles (EVs) that effectively distinguished people with localized breast cancer from cancer-free controls. Here we report on a significant refinement to the test methodology allowing the assessment of the lipid signature directly from plasma samples and its performance, with the aim of advancing the commercial viability of the test as we move towards clinical application. Methods Lipids in EVs from fasted breast cancer and control blood samples (4 separate cohorts (n = 793)) were extracted and analysed by liquid chromatography-high resolution mass spectrometry (LC-HRAM-MS). Over 400 manually curated lipids were quantified. From these, an independent review and retrospective analysis of the data established a lipid signature. The lipid signature was modelled on each of the cohorts using leave-one-out internal cross-validation. Following variable selection, a lipid signature capable of distinguishing breast cancer samples from controls was derived. Furthermore, we investigated if the lipid signature can be assessed from plasma instead of EVs with the aim of further streamlining the process. We analysed the lipids in cancer and control plasma samples (n = 256) previously used for EV preparations, corresponding to patients from Cohorts 3 and 4, and applied the signature derived using EVs on plasma lipidomic data. NIST Standard Reference Material (SRM) 1950-Metabolites in Frozen Human Plasma was used for inter-laboratory quality control. Results Breast cancer subjects were differentiated from controls by the lipid signature with an area under the curve (AUC) of 0.77–0.89 across four cohorts. Assessing the signature directly from plasma, the test achieved a comparable AUC of 0.84. This improvement would make the test more clinically viable and easier to perform. Conclusion We derived a lipid signature, which shows high potential for distinguishing breast cancer samples from controls directly from plasma instead of EVs, reducing the test complexity. Ongoing studies will optimize the plasma lipidomic signature and prospectively compare the test against mammographic and pathological diagnoses.

Challenges and gaps in regulating medical laboratories in India

Accurate diagnosis is an essential component of healthcare delivery. However, research on the delivery of diagnostic services is lacking in low- and middle-income countries. This article examines the issues related to the provision of medical laboratory services in India, including licencing, geographic distribution, charging practices, quality, personnel requirements, information sharing, and newer technologies that impact the sector. The challenges and gaps in regulatory mechanisms governing these services are discussed, highlighting the need for improvements. Legislation to regulate medical laboratories in many Indian states is either outdated or non-existent, with some states recently updating or enacting their laws. A registry of medical laboratories in the country will assist in assessing and meeting the shortfall. Universal adoption of external and inter-laboratory quality control mechanisms will help in standardization and ensuring quality. Clarity and consensus on who can operate medical laboratories and the responsibility of different cadres of technical staff are required. The provision for making information on registered laboratories publicly available under the Central and some state legislations can be very useful to the users in choosing laboratories. Mandatory reporting to the government by both public- and private-sector laboratories will help in maintaining data on disease burden and in planning health services. However, the lack of data protection laws in the country creates the potential for violation of the users’ privacy when laboratories store data digitally and report it online on government web portals. Caution is warranted in the use of newer technologies until the regulations governing these matters are strengthened. A combination of voluntary and statutory mechanisms such as accreditation and regulation would be useful instruments for ensuring quality in diagnostic services. Research on the effectiveness of existing provisions at the state level would help in understanding their impact and suggest ways of further improvement.

Expert consensus on the morphological evaluation of human cleavage-stage embryos and blastocysts.

Expert consensus on the morphological evaluation of human cleavage-stage embryos and blastocysts.

Reference Materials for the Activity Concentration of Technogenic Radionuclides and the Mass Fraction of Elements Based on the Soil Matrix of the Semipalatinsk Test Site

The application of reference materials for the composition and properties of natural objects with certified characteristics is the main instrument for ensuring the correctness of the obtained analytical information in radioecological, geological, and other studies. The article presents the experience of the branch of the Institute of Radiation Safety and Ecology of the National Nuclear Center of the Republic of Kazakhstan in the development and certification of reference materials containing technogenic radionuclides and mass fractions of elements. The soil selected from the sites of underground and surface nuclear tests at the «Experimental field» and «Balapan» sites of the former Semipalatinsk Test Site, which has a diverse radionuclide composition (natural and technogenic radionuclides) with a wide range of chemical elements, was chosen as the starting material for production of reference materials. The main purpose of the work is the certification of two reference materials: reference material for the activity concentration of 137Cs, 90Sr, the mass fraction of Zn, Cu, Pb, Cd, Co, Fe, Mn, As in the soil cover of the Semipalatinsk Test Site (KZ.04.01.00007–2020) and reference material for the activity concentration of 152Eu, 60Co, the mass fraction of Zn, Cu, Pb, Cd, Co, Fe, Mn, As in the soil cover of the Semipalatinsk Test Site (KZ.04.01.00008–2020).All procedures necessary for the creation of reference materials were carried out: separation of the magnetic fraction from the bulk of the material, grinding of the material, control sieve of the material, as well as homogenization with subsequent analytical studies to certify the parameters of reference materials. The methods of gamma spectrometry, beta spectrometry, mass spectrometry, and combined measurement results processing were applied. The results of an interlaboratory comparative test to determine the certified value of the concentrations of the specified radionuclides and elements are given.Reference materials are soil samples dried to an air-dry state, grinded to a particle size of less than 60 µm, and packaged in hermetically sealed polypropylene containers weighing 200 g. Reference materials have been included in the register of the state system for ensuring the uniformity of measurements and approved as state reference materials of the Republic of Kazakhstan. The scope of reference materials is to provide interlaboratory quality control of tests of analytical laboratories specialized in conducting radioecological complex studies, as well as the development and validation of analytical measurement procedures.

Quantification of Minimal Disease by Digital PCR in ALK-Positive Anaplastic Large Cell Lymphoma: A Step towards Risk Stratification in International Trials?

Simple SummaryDetection of minimal disease in blood or bone marrow is associated with high relapse risk in children with anaplastic large cell lymphoma (ALCL). The persistence of minimal residual disease after one course of chemotherapy indicates a relapse risk of 80%. While quantification of minimal disease might further improve the identification of high-risk patients, the assays used for quantification currently are not transferable between multiple laboratories. We aimed to test a digital PCR method (dPCR) for comparison of minimal disease quantification between two laboratories and the usefulness of quantification for risk stratification of children with ALCL. Quantification of minimal disease by dPCR was concordant between laboratories and allowed identification of patients at very high risk for relapse. Qualitative detection of minimal residual disease after one course of chemotherapy sufficed to identify children at the highest risk of treatment failure. International dissemination of this assay will allow patient selection for new targeted treatment approaches.Minimal disseminated and residual disease (MDD/MRD) analyzed by qualitative PCR for NPM-ALK fusion transcripts are validated prognostic factors in pediatric ALK-positive anaplastic large cell lymphoma (ALCL). Although potentially promising, MDD quantification by quantitative real-time PCR in international trials is technically challenging. Quantification of early MRD might further improve risk stratification. We aimed to assess droplet digital PCR for quantification of minimal disease in an inter-laboratory setting in a large cohort of 208 uniformly treated ALCL patients. Inter-laboratory quality control showed high concordance. Using a previously described cut-off of 30 copies NPM-ALK/104 copies ABL1 (NCN) in bone marrow and peripheral blood, MDD quantification allowed identification of very high-risk patients (5-year PFS% 34 ± 5 for patients with ≥30 NCN compared to 74 ± 6 and 76 ± 5 for patients with negative or <30 NCN, respectively, p < 0.0001). While MRD positivity was confirmed as a prognostic marker for the detection of very high-risk patients in this large study, quantification of MRD fusion transcripts did not improve stratification. PFS% was 80 ± 5 and 73 ± 6 for MDD- and MRD-negative patients, respectively, versus 35 ± 10 and 16 ± 8 for MRD-positive patients with <30 and ≥30 NCN, p < 0.0001. Our results suggest that MDD quantification by dPCR enables improved patient stratification in international clinical studies and patient selection for early clinical trials already at diagnosis.

External quality assessment of COVID-19 real time reverse transcription PCR laboratories in India.

Sudden emergence and rapid spread of COVID-19 created an inevitable need for expansion of the COVID-19 laboratory testing network across the world. The strategy to test-track-treat was advocated for quick detection and containment of the disease. Being the second most populous country in the world, India was challenged to make COVID-19 testing available and accessible in all parts of the country. The molecular laboratory testing network was augmented expeditiously, and number of laboratories was increased from one in January 2020 to 2951 till mid-September, 2021. This rapid expansion warranted the need to have inbuilt systems of quality control/ quality assurance. In addition to the ongoing inter-laboratory quality control (ILQC), India implemented an External Quality Assurance Program (EQAP) with assistance from World Health Organization (WHO) and Royal College of Pathologists, Australasia. Out of the 953 open system rRTPCR laboratories in both public and private sector who participated in the first round of EQAP, 891(93.4%) laboratories obtained a passing score of > = 80%. The satisfactory performance of Indian COVID-19 testing laboratories has boosted the confidence of the public and policy makers in the quality of testing. ILQC and EQAP need to continue to ensure adherence of the testing laboratories to the desired quality standards.

Inter-laboratory testing as a strategy for external quality assessment for qualitative detection of SARS-CoV-2 by real-time RT-PCR testing in India.

To implement the strategy of test, track and treat to tackle the ongoing COVID-19 pandemic, the number of real-time RT-PCR–based testing laboratories was increased for diagnosis of SARS-CoV-2 in the country. To ensure reliability of the laboratory results, the Indian Council of Medical Research initiated external quality assessment (EQA) by deploying inter-laboratory quality control (ILQC) activity for these laboratories by nominating 34 quality control (QC) laboratories. This report presents the results of this activity for a period of September 2020 till November 2020. A total of 597 laboratories participated in this activity and 86 per cent of these scored ≥90 per cent concordance with QC laboratories. This ILQC activity showcased India’s preparedness in quality diagnosis of SARS-CoV-2.

Evaluation of the Bio-Evolution Microsporidia generic and typing real-time PCR assays for the diagnosis of intestinal microsporidiosis.

Cases of intestinal microsporidiosis infection are underestimated and affect both immunocompromized and immunocompetent patients. Real-time PCR is superseding microscopic examination for its diagnosis in medical analysis laboratories. However, few manufacturers include microsporidia in their PCR panel for the diagnosis of infectious gastroenteritis. Here, we evaluated the performances of the real-time PCR assays microsporidia generic and microsporidia typing (Bio-Evolution, France) on the Rotor-Gene Q real-time PCR cycler (Qiagen, France). We included 45 negative and 44 positive stool samples for Enterocytozoon bieneusi (n=34, with various genotypes), Encephalitozoon intestinalis (n=4), Encephalitozoon hellem (n=4), and Encephalitozoon cuniculi (n=2). We also studied a four-year survey of an inter-laboratory quality control program including 9 centers that used this commercial assay. Sensitivity and specificity of the microsporidia generic assay were 86.4% and 93.3%, respectively. Encephalitozoon hellem and Encephalitozoon cuniculi were detected by the microsporidia generic PCR assay but not by the microsporidia typing PCR assay. These results were consistent with the results of the inter-laboratory quality control program. In conclusion, Bio-Evolution Real-time PCR assays are useful tools for intestinal microsporidiosis, but negative results for microsporidia typing assays require supplementary analyses to confirm E. hellem or E. cuniculi infections.

The duration and specificity of the humoral immune response to SARS-CoV-2

Background. Our assumption that immunity after COVID-19 will persist has been fully confirmed in the researches already conducted. Our work is a continuation of research that demonstrates the results obtained 12 months of determining the humoral response in patients after COVID-19.&#x0D; Materials and methods. The research involved 42 individuals. All subjects had a positive PCR test for COVID-19. At certain intervals, from 40 to 240 days, individuals in the group were tested for IgG SARS-CoV-2. The last step was to check the level of IgG to the COVID-19 nucleocapsid and spike protein in the research group for 360 days from the onset of the disease. A private certified laboratory in Kyiv, the “DNA Laboratory”, was involved. Patients were tested for antibodies to COVID-19 by ELISA using serology COVID-19 test systems VitroTest (Ukraine). The immunological laboratory of the Institute of Pediatrics, Obstetrics and Gynecology was used in parallel for interlaboratory quality control. The results of the research coincided.&#x0D; Results. The level of class G immunoglobulins to nucleocapsid in the subjects has gradually decreased over 8 months. It is noteworthy that in the period from 40 to 150 days in all 42 patients (100 %) antibodies did not disappear. Decreasing of antibodies occurred between 150 and 240 days. However, the data obtained for 360 days significantly changed the picture. In a certain part of the subjects, who had low or even negative levels of antibodies for 8 months, as of 12 months, the level of immunoglobulin (Ig) class G again rose above the threshold value. Thus, we see that from the group of 42 people 92.8 % have positive antibodies to the nucleocapsid, and 7.2 %.&#x0D; Conclusions. The data obtained illustrate that in the study group within 12 months after SARS-CoV-2, the vast majority of individuals remain with specific antibodies to the nucleocapsid and spike-protein.

Airborne fungal spore monitoring: between analyst proficiency testing

This study presents the results of a Europe-wide training and Quality Control (QC) exercise carried out within the framework of the European Aerobiology Society’s QC Working Group. The main aim of this exercise was to examine the feasibility of carrying out a QC exercise for fungal spore monitoring in Europe, using a similar methodology to the one previously used for pollen. The QC survey was conducted in two parts: (1) Coordinators of national and regional aerobiological networks in Europe involved in the monitoring of atmospheric fungal spores were invited to complete a questionnaire survey related to their network and asked whether they were interested in taking part in an external inter-laboratory QC exercise; (2) Participating networks performed an inter-laboratory ring test with the same sample slide in order to determine the reproducibility of identifying and counting two fungal spore taxa (Alternaria and Epicoccum) in air samples collected by a Hirst-type volumetric spore trap. Participants were instructed to read five separate longitudinal transects in the “effective collecting area” of the slide. Reproducibility of analysis was determined following the method previously used in the European Aerobiology Society’s QC exercises for pollen. Thirty-two counters from 16 national or regional networks in Europe participated in the QC exercise. Coefficients of Variation (CV%) ranged from 23.0 to 22.5 when reading one transect and from 14.0 to 16.0 when reading five transects for Alternaria and Epicoccum, respectively. Considering a CV% of 30 as the limit for fungal spores, no significant differences were observed between the absolute errors from two, three, four and five transects. The only significant difference was between one and five transects. We recommend that fungal spore analysis should be carried out on about 5% of the slide (two transects in this study) because results were not significantly different to five transects.

Interlaboratory proficiency test in aerobiology using virtual slides – feasibility study

This study examines the use of Virtual Slide Images with the aim of assessing their efficacy and usability in comparison to traditional microscopy with glass slides for the Quality Control of aerobiological samples. Three glass microscopy slides containing samples of airborne pollen were digitised. Six counters from two laboratories examined the glass slides and their data were used to calculate assigned values and acceptable coefficients of variation (CV%) for seven pollen types. A total of 24 analysts from 12 countries examined the virtual slides using specialist OlyVIA software. Data from traditional glass and virtual slides were entered into tests for repeatability and intralaboratory reproducibility following the norm EN 16868:2019. Participants also completed a questionnaire reflecting on the efficacy and usability of Virtual Slide Images for interlaboratory Quality Control. Data from traditional glass and virtual slides were comparable but CV% were generally larger for virtual slides than glass slides. Participants who examined < 10% of the slide were more likely to produce results outside the limits of the study. The use of virtual slide technology is not for everyone and, in the current study, we found that opinion was polarised but it was interesting to note that there were no differences in response based on years of experience. There are advantages and disadvantages of the two methods, and we recommend virtual slides are used as an adjunct to glass slides for use in aerobiology Quality Control and other aspects of palynological training and assessment.

The top-down approach to measurement uncertainty: which formula should we use in laboratory medicine?

IntroductionBy quantifying the measurement uncertainty (MU), both the laboratory and the physician can have an objective estimate of the results’ quality. There is significant flexibility on how to determine the MU in laboratory medicine and different approaches have been proposed by Nordtest, Eurolab and Cofrac to obtain the data and apply them in formulas. The purpose of this study is to compare three different top-down approaches for the estimation of the MU and to suggest which of these approaches could be the most suitable choice for routine use in clinical laboratories.Materials and methodsImprecision and bias of the methods were considered as components of the MU. The bias was obtained from certified reference calibrators (CRC), proficiency tests (PT), and inter-laboratory internal quality control scheme (IQCS) programs. The bias uncertainty, the combined and the expanded uncertainty were estimated using the Nordtest, Eurolab and Cofrac approaches.ResultsUsing different approaches, the expanded uncertainty estimates ranged from 18.9-40.4%, 18.2-22.8%, 9.3-20.9%, and 7.1-18.6% for cancer antigen (CA) 19-9, testosterone, alkaline phosphatase (ALP), and creatinine, respectively. Permissible values for MU and total error ranged from 16.0-46.1%, 13.1-21.6%, 10.7-26.2%, and 7.5-17.3%, respectively.ConclusionThe bias was highest using PT, followed by CRC and IQCS data, which were similar. The Cofrac approach showed the highest uncertainties, followed by Eurolab and Nordtest. However, the Eurolab approach requires additional measurements to obtain uncertainty data. In summary, the Nordtest approach using IQCS data was therefore found to be the most practical formula.

The performance evaluation of unassayed biochemistry serum controls

Objective To evaluate the inter-bottle variations, stability in consumption and interchangeability of unassayed biochemistry serum controls. Methods Comparison between unassayed serum controls from a domestic Pretrol® and an international Bio-Rad manufacturer was conducted in department of laboratory, in May 2016, with Roche Cobas 8000, Roche Hitachi 7600 and Siemens 2400 modular analyzer. The inter-bottle variation was determined by monitoring the inter-batch variation of 10 bottles of control samples after eliminating the intra-batch variation from the same bottle. Stability in consumption was determined as the precision after 7 days storage under 2 ℃ to 8 ℃ or 30 days of storage under -20 ℃ since reconstitution. The interchangeability was determined as the precisionbetween the controls from different manufacturers for the same test. Results The inter-bottle imprecision of controls from domestic manufacturer for 13 biochemistry tests (CV concentration 1/CV concentration 2) were potassium (0.26%/0.42%), sodium (0.26%/0.21%), phosphorus (0.00%/0.62%), cholesterol (0.56%/0.54%), total protein (0.52%/0.33%), albumin (0.44%/2.00%), alanine aminotransferase (1.72%/0.57%), γ-glutamylaminotransferase (0.52%/0.62%), aspartate aminotransferase (3.10%/1.09%), lactate dehydrogenase (0.76%/0.91%), alkaline phosphatase (1.13%/0.97%), amylase (0.30%/0.39%) and glucose (0.00%/0.40%). The stability in consumption of the controls from the domestic manufacturer (CV concentration 1/CV concentration 2 under 2 ℃ to 8 ℃storage; CV concentration 1/CV concentration 2 under -20 ℃ storage) were potassium (1.06%/0.36%; 0.74%/0.48%), sodium (0.49%/0.59%; 0.72%/0.65%), phosphorus (0.95%/0.80%; 1.43%/0.84%), cholesterol (1.49%/1.58%; 2.17%/1.80%), total protein (0.84%/0.75%; 1.60%/1.68%), albumin (1.33%/2.28%; 1.94%/2.43%), alanine aminotransferase (1.41%/0.51%; 3.24%/1.60%) γ-glutamylaminotransferase (1.16%/1.16%; 2.85%/2.49%), aspartate aminotransferase (4.37%/2.14%; 2.99%/1.31%), lactate dehydrogenase (2.70%/2.54%; 3.84%/2.97%), alkaline phosphatase (2.63%/1.96%; 2.31%/2.10%), amylase (0.95%/2.19%; 1.58%/1.38%) and glucose (0.60%/0.48%; 1.41%/1.55%). The Inter-bottle variation and stability in consumption of biochemistry test unassayed controls from the domestic manufacturer were compatible for clinical assay according to the CV% specification from the Clinical Biochemistry Test Quality Requirement (WS/T 403-2012). The imprecision of the controls from both the domestic and international manufacturers (CVp concentration 1/CVp concentration2; CVq concentration 1/CVq concentration 2) were potassium (0.52%/0.46%; 2.39%/0.47%), sodium (0.30%/0.17%; 0.81%/0.47%), phosphorus (2.72%/1.11%; 4.57%/2.07%), cholesterol (0.29%/1.38%; 2.94%/1.81%), total protein (0.66%/2.46%; 1.85%/2.54%), alkaline phosphatase (2.67%/4.66%; 3.58%/8.55%), total bilirubin (5.71%/5.09%; 9.55%/7.41%), albumin (1.10%/2.61%; 4.79%/1.93%), alanine aminotransferase (6.42%/1.25%; 5.74%/1.63%), γ-glutamylaminotransferase (2.27%/4.35%; 4.38%/0.74%), aspartate aminotransferase (0.56%/2.84%; 0.91%/2.11%) and lactate dehydrogenase (2.36%/2.47%; 3.10%/1.52%). The interchangeability of serum controls from domestic manufacturer was better than clinical serum samples. Conclusion The unassayed serum biochemistry test controls from domestic manufacturer are suitable for the intra-laboratory quality control and showed a promising compatibility for inter-laboratory quality control usage. Key words: Quality control; Clinical chemistry tests; Diagnostic tests,routine; Clinical laboratory techniques

Quality Assurance In The Medical Microbiology Laboratory

Abstract In each laboratory, a quality assurance program should be developed in order to obtain reliable results and to fulfil the requirements of quality standards in the field of microbiological laboratory tests. Microbiological diagnostics makes it possible to determine the etiological agent of infection and allow the selection of an appropriate therapy. The quality of test results are affected by pre-laboratory, laboratory and post-laboratory steps, which should be checked regularly. Constant internal quality control of performance in the laboratory and participation in external quality control programmes may ensure the quality of results. Internal quality control of the tests at all stages of routine microbiological diagnostics in the laboratory facilitates constant monitoring of the quality of results. Participation in interlaboratory external quality control programmes permits the quality of performance of tests routinely used in a laboratory to be assessed. 1. Introduction. 2. Quality assurance programme. 2.1. Factors affecting quality. 3. Internal quality control. 3.1. Quality control of identification tests. 3.2. Internal quality control of antimicrobial susceptibility testing and detecting resistance mechanisms. 3.3. Internal quality control of automated systems for identification and susceptibility testing. 4. External quality control. 4.1. External quality assurance programme participation rules. 5. Summary

Harmonizing lipidomics: NIST interlaboratory comparison exercise for lipidomics using SRM 1950–Metabolites in Frozen Human Plasma

As the lipidomics field continues to advance, self-evaluation within the community is critical. Here, we performed an interlaboratory comparison exercise for lipidomics using Standard Reference Material (SRM) 1950–Metabolites in Frozen Human Plasma, a commercially available reference material. The interlaboratory study comprised 31 diverse laboratories, with each laboratory using a different lipidomics workflow. A total of 1,527 unique lipids were measured across all laboratories and consensus location estimates and associated uncertainties were determined for 339 of these lipids measured at the sum composition level by five or more participating laboratories. These evaluated lipids detected in SRM 1950 serve as community-wide benchmarks for intra- and interlaboratory quality control and method validation. These analyses were performed using nonstandardized laboratory-independent workflows. The consensus locations were also compared with a previous examination of SRM 1950 by the LIPID MAPS consortium. While the central theme of the interlaboratory study was to provide values to help harmonize lipids, lipid mediators, and precursor measurements across the community, it was also initiated to stimulate a discussion regarding areas in need of improvement.

Colombian results of the interlaboratory quality control exercise 2015

Currently, all agencies of conformity assessment testing laboratory favor the participation in proficiency testing as a mechanism for quality assurance. In Colombia, the Genes Laboratory has been designated, since 2008, to perform, design and implement proficiency testing for all the interested laboratories. In this report, the results of Colombian exercise Interlaboratory Quality Control for the year 2015 are presented. The exercise consisted of one practical component, one theoretical mandatory component, and an optional theoretical component. Twenty laboratories participated, representing six different countries of Latin America and the Caribbean. For the practical component each participant laboratory received; (1) samples of blood, saliva, and semen stains, in this part they should report the routine own laboratory markers for each sample, (2) three optional theoretical cases of varying complexity, (3) a mandatory theoretical approach about a biological relationship of paternal grandparents – granddaughter case. In the last two components of the exercise, they had to submit only the calculations. For the practical component the consensus of 70 STR markers, distributed between autosomal and linked to the sex chromosomes, was achieved with an error rate of 0.80% in genotyping, 1.0% nomenclature and/or format discrepancies and 3.8% non-reporting. On the other hand, 99.4% of the reported values were correct, only two values were not correct (0.6%) but were within the range of 5% of the correct value, being acceptable values within the rules of the exercise. This inter-laboratory exercise has become an important mechanism for quality assurance and ongoing training in the region.