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1,805 result(s) for "proficiency testing"
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Importance of EQA/PT for the detection of genetic variants in comprehensive cancer genome testing
Comprehensive genomic profiling (CGP) is increasingly used as a clinical laboratory test and being applied to cancer treatment; however, standardization and external quality assessments (EQA) have not been fully developed. This study performed cost-effective EQA and proficiency tests (PT) for CGP testing among multiple institutions those belong to the EQA working group of Japan Association for Clinical Laboratory Science (JACLS). This study revealed that preanalytical processes, such as derived nucleic acids (NA) extraction from formalin fixed paraffine embedded (FFPE) samples, are critical. First, EQA with extracted DNA from cell lines showed a detection rate of 100% (9 out of 9) in KRAS (c.38G > A; p.G13D), PIK3CA (p.H1047R), and B-Raf proto-oncogene, serine/threonine kinase ( BRAF ) (c.1799 T > A; p.V600E) in cases of > 10% variant allele frequency (VAF). However, BRAF (c.1799 T > A; p.V600E) detection decreased to 67% (6 out of 9) for a VAF of 4.9%. Second, when DNA was extracted from FFPE samples, pathogenic variants and variants with companion diagnostic indications were detected in all 10 participating laboratories. Each variant had < 20% VAFs on average (8.1–19.1%) and wide variability among laboratories was observed (relative standard deviation, 13–60%). Nonetheless, BRAF (c.1798_1799delinsAA; p.V600K) of 8.1% VAF, EGFR (c.2235_2249del; p.E746_A750del) of 9.7% VAF, and EGFR (c.2254_2277del; p.S752_I759del) of 9.8% VAF were detected with 70% (7/10), 70% (7/10), and 60% (6/10) frequency, respectively. Therefore, 10% VAF in pre-analytic processing for DNA extraction from FFPE was critical for variant detection in CGP analysis. Further, incorrect results were reported in case independent variant calling of BRAF; c.1798_1799delinsAA (p.V600K) was mistakenly interpreted as c.1798G > A, and c.1799 T > A was on the other strand. In conclusion, the EQA/PT among 10 institutes with common samples revealed the importance of VAF in pre-analysis and helped us understand the significance of the pipeline and common pitfalls usually ignored by the internal quality control in a single institute.
Towards harmonization of microscopy methods for malaria clinical research studies
Microscopy performed on stained films of peripheral blood for detection, identification and quantification of malaria parasites is an essential reference standard for clinical trials of drugs, vaccines and diagnostic tests for malaria. The value of data from such research is greatly enhanced if this reference standard is consistent across time and geography. Adherence to common standards and practices is a prerequisite to achieve this. The rationale for proposed research standards and procedures for the preparation, staining and microscopic examination of blood films for malaria parasites is presented here with the aim of improving the consistency and reliability of malaria microscopy performed in such studies. These standards constitute the core of a quality management system for clinical research studies employing microscopy as a reference standard. They can be used as the basis for the design of training and proficiency testing programmes as well as for procedures and quality assurance of malaria microscopy in clinical research.
Challenges and improvements in HER2 scoring and histologic evaluation: insights from a national proficiency testing scheme for breast cancer diagnosis in China
Background In 2022, our team launched the pioneering national proficiency testing (PT) scheme for the pathological diagnosis of breast cancer, rapidly establishing its credibility throughout China. Aiming to continuously monitor and improve the proficiency of Chinese pathologists in breast pathology, the second round of the PT scheme was initiated in 2023, which will expand the number of participating institutions, and will conduct a nationwide investigation into the interpretation of HER2 0, 1+, and 2+/FISH- categories in China. Methods The methodology employed in the current round of PT scheme closely mirrors that of the preceding cycle in 2022, which is designed and implemented according to the “Conformity assessment—General requirements for proficiency testing”(GB/T27043—2012/ISO/IEC 17043:2010). More importantly, we utilized a statistics-based method to generate assigned values to enhance their robustness and credibility. Results The final PT results, published on the website of the National Quality Control Center for Cancer ( http://117.133.40.88:3927 ), showed that all participants passed the testing. However, a few institutions demonstrated systemic biases in scoring HER2 0, 1+, and 2+/FISH- with accuracy levels below 59%, considered unsatisfactory. Especially, the concordance rate for HER2 0 cases was only 78.1%, indicating challenges in distinguishing HER2 0 from low HER2 expression. Meanwhile, areas for histologic type and grade interpretation improvement were also noted. Conclusions Our PT scheme demonstrated high proficiency in diagnosing breast cancer in China. But it also identified systemic biases in scoring HER2 0, 1+, and 2+/FISH- at some institutions. More importantly, our study highlighted challenges in the evaluation at the extreme lower end of the HER2 staining spectrum, a crucial area for further research. Meanwhile, it also revealed the need for improvements in interpreting histologic types and grades. These findings strengthened the importance of robust quality assurance mechanisms, like the nationwide PT scheme conducted in this study, to maintain high diagnostic standards and identify areas requiring further training and enhancement.
Factors affecting the accuracy of blood alcohol determinations in clinical and forensic laboratories in Italy: Results of a 7-year proficiency testing study
The results of a 7-year proficiency study involving Italian laboratories measuring blood alcohol concentration (BAC) are reported. Two blood samples spiked with known amounts of ethanol were sent for analysis twice per year to approximately 50 laboratories across Italy. The blood samples were prepared according to ISO standards, which included optimized transport and storage conditions to ensure ethanol stability. Participants completed an online questionnaire detailing their analytical results along with other analytical details, including the use of GC-FID or GC-MS, storage temperature, time between sample delivery and analysis, reference materials, replicate determinations, and volume of blood aliquot. The participants also confirmed whether or not they were accredited and what the measurement uncertainty was for determination of BAC. The results from analysis of 1171 blood samples (after elimination of outliers) were evaluated by calculating z-scores using robust statistical methods. The inter-laboratory standard deviation (SD) increased with blood alcohol concentration (r = 0.94, p < 0.001). Notably, a significant reduction in robust SD was observed between 2017 and 2023 (p = 0.01). The use of matrix-matched certified reference materials gave more accurate results with mean z-scores closer to zero. The choice of analytical method, storage conditions, time delays, and laboratory accreditation did not significantly influence z-scores. This study revealed that regular participation in inter-laboratory proficiency programs did contribute to improving analytical performance. The choice of certified reference material was the principal determinant of the accuracy of the results. [Display omitted] •Results from a 7-year laboratory proficiency survey in Italy are reported.•Twice annually ∼50 labs analyzed two blood samples spiked with ethanol.•Ethanol concentrations in 1171 blood samples were evaluated using robust statistics.•Inter-lab variance increased with ethanol concentration and decreased over time.•Matrix-matched with certified reference standards was key to improving accuracy.
Proficiency testing of diagnosis in histopathology and immunohistochemistry of breast pathology in China: results from a pilot work of National Single Disease Quality Control Program for breast cancer
Aim Pathologists are currently supposed to be aware of both domestic and international guidelines for breast cancer diagnosis, but it is unclear how successfully these guidelines have been integrated into routine clinical practice in China. Thus, this national proficiency testing (PT) scheme for breast pathology was set up to conduct a baseline assessment of the diagnostic capability of pathologists in China. Methods This national PT plan is designed and implemented according to the “Conformity assessment—General requirements for proficiency testing” (GB/T27043—2012/ISO/IEC 17043:2010). Five cases of breast cancer with six key items, including histologic type, grade, ER, PR, HER2, and Ki67, were selected for testing among 96 participants. The final PT results were published on the website of the National Quality Control Center for Cancer ( http://117.133.40.88:3927/cn/col22/362 ). Results Our study demonstrated that the median PT score was 89.5 (54–100). Two institutions with scores < 67 were deemed unacceptable. The accuracy of histologic type, ER, PR, HER2, and Ki67 was satisfactory (all > 86%). However, the histologic grade showed low accuracy (74.0%). The unacceptable results mainly included incorrect evaluation of histologic grade (36.7%), inaccurate evaluation of ER/PR/HER2/Ki67 (28.2%), incorrect identification of C-AD as IBC-NST (15.7%), inappropriate use of 1+/2+/3+ rather than staining percentage for ER/PR (6.1%), misclassification of ER/PR < 1% weak expression as positive staining (1.4%), and no evaluation of histologic grade in ILC, MC, and IMC (5.8%). Conclusions our nationwide PT program exhibited a satisfactory baseline assessment of the diagnostic capability of pathologists in China. More importantly, we identify some areas for further improvement.
The development and implementation of a proficiency testing program for SARS-CoV-2 using dried tube specimens in resource-limited countries
Introduction When COVID-19 hit the world in 2019, an enhanced focus on diagnostic testing for SARS-CoV-2 was essential for a successful pandemic response. Testing laboratories stretched their capabilities for the new coronavirus by adopting different test methods. The necessity of having external quality assurance (EQA) mechanisms was even more critical due to this rapid expansion. However, there was a lack of experience in providing the necessary SARS-CoV-2 EQA materials, especially in locations with constrained resources. Objective We aimed to create a PT (Proficiency testing) programme based on the Dried Tube Specimens (DTS) method that would be a practical option for molecular based SARS-CoV-2 EQA in Low- and Middle-Income Countries. Methods Based on previous ISO/IEC 17043:2010 accreditation experiences and with assistance from the US Centers for Disease Control and Prevention, The Supranational Reference Laboratory of Uganda (adapted the DTS sample preparation method and completed a pilot EQA program between 2020 and 2021. Stability and panel validation testing was conducted on the designed materials before shipping to pilot participants in six African countries. Participants received a panel containing five SARS-CoV-2 DTS samples, transported at ambient conditions. Results submitted by participants were compared to validation results. Participants were graded as satisfactory (≥ 80%) or unsatisfactory (< 80%) and performance reports disseminated. Results Our SARS-CoV-2 stability experiments showed that SARS-CoV-2 RNA was stable (-15 to -25 °C, 4 to 8 °C, (18 to 28 °C) room temperature and 35 to 38 °C) as well as DTS panels (4 to 8 °C, 18 to 28 °C, 35 to 38 °C and 45 °C) for a period of 4 weeks. The SARS-CoV-2 DTS panels were successfully piloted in 35 test sites from Zambia, Malawi, Mozambique, Nigeria, and Seychelles. The pilot results of the participants showed good accuracy, with an average of 86% (30/35) concordance with the original SARS CoV-2 expectations. Conclusion The SARS-CoV-2 DTS PT panel is reliable, stable at ambient temperature, simple to prepare and requires minimal resources.
Identification of SARS-CoV-2 in a Proficiency Testing Program
Abstract Objectives At the onset of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic in the United States, testing was limited to the Centers for Disease Control and Prevention–developed reverse transcription polymerase chain reaction assay. The urgent and massive demand for testing prompted swift development of assays to detect SARS-CoV-2. The objective of this study was to assess the accuracy of these newly developed tests. Methods The American Proficiency Institute sent 2 test samples to 346 clinical laboratories in order to assess the accuracy of SARS-CoV-2 assays. The positive sample, containing 5,175 viral copies/mL, was fully extractable with SARS-CoV-2 viral capsid protein and RNA. The negative sample, with 3,951 viral copies/mL, contained recombinant virus particles with sequences for targeting human RNAase P gene sequences. Results Of the laboratories submitting results, 97.4% (302/310) correctly detected the virus when present and 98.3% (296/301) correctly indicated when the virus was not present. Among incorrect results reported in this proficiency challenge, 76.9% (10/13) were likely related to clerical error. This accounts for 1.6% (10/611) of all reported results. Conclusions Overall performance in this SARS-CoV-2 RNA detection challenge was excellent, providing confidence in the results of these new molecular tests and assurance for the clinical and public health decisions based on these test results.
CAP/ACMG proficiency testing for biochemical genetics laboratories: a summary of performance
Testing for inborn errors of metabolism is performed by clinical laboratories worldwide, each utilizing laboratory-developed procedures. We sought to summarize performance in the College of American Pathologists’ (CAP) proficiency testing (PT) program and identify opportunities for improving laboratory quality. When evaluating PT data, we focused on a subset of laboratories that have participated in at least one survey since 2010. An analysis of laboratory performance (2004 to 2014) on the Biochemical Genetics PT Surveys, a program administered by CAP and the American College of Medical Genetics and Genomics. Analytical and interpretive performance was evaluated for four tests: amino acids, organic acids, acylcarnitines, and mucopolysaccharides. Since 2010, 150 laboratories have participated in at least one of four PT surveys. Analytic sensitivities ranged from 88.2 to 93.4%, while clinical sensitivities ranged from 82.4 to 91.0%. Performance was higher for US participants and for more recent challenges. Performance was lower for challenges with subtle findings or complex analytical patterns. US clinical biochemical genetics laboratory proficiency is satisfactory, with a minority of laboratories accounting for the majority of errors. Our findings underscore the complex nature of clinical biochemical genetics testing and highlight the necessity of continuous quality management.
Conventional Cytogenetic Analysis of Solid Tumor Abnormalities: A 25-Year Review of Proficiency Test Results from the College of American Pathologists/American College of Medical Genetics and Genomics Cytogenetics Committee
Background: The joint College of American Pathologists/American College of Medical Genetics and Genomics Cytogenetics Committee works to ensure the competency and proficiency of clinical cytogenetic testing laboratories through proficiency testing (PT) programs for various clinical tests offered by such laboratories, including the evaluation of cytogenetic abnormalities in solid tumors. Methods: Review and analyze 25 years (1999–2023) of solid tumor chromosome analysis PT results, utilizing G-banded karyograms. A retrospective review of results from 1999 to 2023 was performed, identifying the challenges addressing solid tumors. The chromosomal abnormalities and overall performance were evaluated. Results: A total of 21 solid tumor challenges were administered during the period 1999–2018. No solid tumor challenges were administered during the period 2019–2023. Challenges consisted of metaphase images and accompanying clinical history for the evaluation of numerical and/or structural abnormalities. All 21 cases reached 80% grading consensus for abnormality recognition. However, five cases (24%) failed to reach consensus for nomenclature reporting by participating laboratories. These cases illustrate errors in reporting chromosomal abnormalities, including whole-arm translocations and those involving sex chromosomes. In addition, they highlight the challenges with differentiation of terminal and interstitial deletions, difficulties in identifying correct breakpoints, and omission of brackets in neoplastic cases. Conclusions: This comprehensive 25-year review demonstrates the exceptional proficiency of cytogenetic laboratories in accurately identifying chromosome abnormalities in solid tumors, while also highlighting the challenges of reporting specific types of chromosomal abnormalities.
Nationwide proficiency assessment of bacterial identification and antimicrobial susceptibility testing among 110 laboratories in Lebanon
Introduction: Proficiency testing (PT) is one of the most valuable and important activities for the Clinical Microbiology Laboratories (CML) to enroll in to ensure the accuracy and reliability of results. This first time conducted nationwide study was warranted to assess the PT performance activity among CML in Lebanon. Methodology: Four training and PT activities were organized for 110 nationwide laboratories involved in providing clinical microbiology services. In each PT activity, five different bacterial species were distributed to each laboratory to provide identification (ID) and antimicrobial susceptibility testing (AMST) according to prior discussions and guidelines. Results: The percentages of labs that correctly identified the bacterial species and performed the relevant AMST to it, respectively, were as follows: S. aureus, (100% and 67.8%); Enterococcus faecalis (71% and 82%); Listeria monocytogenes (75% and 61%); Streptococcus agalactiae (86% and 71%); Corynebacterium amycolatum (7% and 33 %); Pseudomonas aeruginosa, (93 % and 53.4%); Klebsiella pneumoniae, (97% and 67.7%); Salmonella typhi ESBL (87 % and 66%); Enterobacter aerogenes (89% and 59%) and Stenotrophomonas maltophilia (84 % and 65%). The resistant types for the species were specified by labs as carbapenem resistant (CR) K. pneumoniae in 78 %, CR E. aerogenes in 34 %, MRSA in 83 %, and VRE in 80.5%. Conclusions: The wide variation as well as the overall humble scoring of accurate results reflects the dire need for the MOPH to establish and maintain a PT activity program, and entrust the reference laboratory to provide continuing education and training sessions.