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Objective:The allowable total error ( TEa),allowable imprecision ( CV)and allowable bias( Bias)were recommended for 34 routine chemistry analytes in China. Methods:According to the performance specification setting mode newly determined at the Milan conference in Italy,the performance specification was derived based on components biological variation (BV)and current state of the art mode. The data(including EQA data and IQC data)of laboratories participating in the routine chemistry and lipids and lipoproteins EQA activities of the national center for clinical laboratories from 2019 to 2021 was collected through clinet-EQA. For the analytes with biological variation(BV)data,compared the'percentage difference′ of EQA data and the'in-control coefficient of variation of the month′ of IQC data of each research analyte with the three levels evaluation criteria derived based on BV,and calculated the percentage difference passing rate and CV passing rate of all batches in each year. When the passing rate reaches 80%,the performance specifications of this level met the requirements of the recommended performance specifications of the analyte. For the analytes without BV data or analytes whose performance specifications at three levels derived based on BV could not be used as recommended standards,the recommended performance specifications are derived based on the current state of the art. After obtaining the recommended TEa and allowable CV for each analyte,used the formula | Bias|≤ TEa-z? CV to derive the recommended allowable bias. Results:The results of TEa ( CV)% recommended by 34 analytes are as follows:K4.7(2),Na4(1.5),Cl4(1.4),Ca5(2),P9.6(3.9),Glu6.4(2.5),Urea8(3),UA12(4.1),Cre11(3.3),TP5(2),Alb5.2(2.4),TC8.6(2.7),TG13.5(5),HDL-C16.5(4.3),LDL-C20.5(6.2),ApoAⅠ16(5.3),ApoB 17.1(5.5),Lp(a) 24.1(10.4),TBil 12.4(5),DBil 20(7.3),ALT16(5),AST13.5(4.8),ALP17.5(4.8),AMY13.1(3.3),CK11.3(3.8),LDH11(3.9),CHE13.4(5.3),LIP20(6.9),Fe13.3(5.2),Mg14(4.5),Cu17.9(6.8),Zn15.1(6.4),γ-GGT10(3.3),α-HBDH18(5.8).The formula | Bias|≤ TEa-z? CV is used to derive the allowable bias of 34 analytes. Conclusions:For 34 clinical routine chemistry quantitative analytes,the allowable total error,allowable imprecision and allowable bias that meet the current state of the art of Chinese laboratories are recommended.
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Background: Six sigma is a powerful tool which can be used by laboratories for assessing the method quality, optimizing Quality Control (QC) procedure, change the number of rules applied, and frequency of controls run .The aim of this study was to quantify the defects or errors in the analytical phase of laboratory testing by sigma metrics and then represent the sigma value in Method Decision Chart.Methods: A retrospective study was conducted in a tertiary care hospital in Bhubaneswar, India. The clinical chemistry laboratory has been NABL accredited for the past 5 years and strictly quality checked. Internal and external quality control data was collected for a period of six months from January - June 2018 for 20 biochemical analytes. Sigma metrics for each parameter was calculated and plotted on method decision chart.Results: The sigma metrics for level 2 indicated that 6 out of the 20 analytes qualified Six Sigma quality performance. Of these seven analytes failed to meet minimum sigma quality performance with metrics less than three and another seven analytes performance with sigma metrics was between three and six. For level 3, the data collected indicated that seven out of 20 analytes qualified Six Sigma quality performance, six analytes had sigma metrics less than 3 and seven analytes had sigma metrics between 3 and 6.Conclusion: In our study Sigma value was highest for amylase and lowest for potassium. Use of alternative methods and/ or change of reagents can be done for potassium to bring the sigma value within an acceptable range.
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Los límites analíticos de desempeño (LAD) forman parte del diseño del programa de control de calidad analítico. Los objetivos de este trabajo fueron determinar imprecisión (CV), error sistemático (ES) y error total (ET) de 14 analitos de Química Clínica en los sectores de planta y de guardia del laboratorio del HIGA O. Alende de Mar del Plata, evaluar su desempeño analítico según variabilidad biológica y comparar los datos obtenidos. Se realizó un estudio retrospectivo con el registro de controles de calidad y se utilizaron los LAD derivados de VB para obtener las especificaciones de calidad para CV, ES y ET. Respecto del CV, cumple con los criterios el 79% en el sector planta y el 64% en el de guardia. Y en cuanto al ET, cumple el 90% y el 75%, respectivamente. En conclusión, aunque la mayoría de los analitos evaluados cumplen al menos con los criterios mínimos establecidos, los resultados ponen de manifiesto la necesidad de mejorar el desempeño analítico. Detectar los tipos de errores presentes en el proceso de laboratorio es el primer paso para instaurar controles de procedimiento y análisis, soluciones que permitirán mejorar la calidad analítica, uno de los pilares que optimizan la seguridad del paciente.
The analytical limits of performance (ALP) are part of the programme design of analytical quality control. The goals of this study were to determine imprecision (VC), systematic error (SE) and total error (TE) of 14 clinical chemistry analytes in the routine and emergency laboratory of HIGA O. Alende of Mar del Plata, to evaluate their analytical performance in accordance with biological variability, and compare the data obtained. A retrospective study was performed using the record of quality controls. The ALP were obtained from BV to get the quality specifications for VC, SE and TE. Regarding VC, 78% of the analytes meet the criteria in the routine laboratory and 64% in the emergency. Regarding TE, in the routine laboratory, 90% meet the TE criteria, and 75% in the emergency. It can be concluded that, although most of the evaluated analytes meet at least the minimum established criteria, the results highlight the need to improve the analytical performance. Detecting the types of errors in the laboratory process is the first step to establish procedural and analysis controls. These are solutions that will improve the analytical quality, one of the pillars to optimize patient safety.
Os limites analíticos de desmpeño (LAD) são parte do desenho do programa de controle de qualidade analítico. Os objetivos deste estudo foram determinar a imprecisão (CV), o erro sistemático (ES) e o erro total (ET) de 14 analitos de Química Clínica nas áreas de planta e de plantão do laboratório HIGA O. Alende de Mar del Plata, avaliar seu desempenho analítico de acordo com a variabilidade biológica e comparar os dados obtidos. Um estudo retrospectivo foi realizado com o registro de controles de qualidade utilizando os LAD derivados de VB para obter as especificações de qualidade para CV, ES e ET. Quanto ao CV, 79% cumpre com os critérios no setor da planta e 64% no setor de plantão. E, quanto ao ET, cumpre 90% e 75% respectivamente. Em conclusão, embora a maioria dos analitos testados cumpra pelo menos com os critérios mínimos estabelecidos, os resultados destacam a necessidade de melhorar o desempenho analítico. Detectar os tipos de erros encontrados no processo de laboratório é o primeiro passo para estabelecer controles de procedimento e análise, soluções que permitirão melhorar a qualidade analítica, um dos pilares que otimizam a segurança do paciente.
Subject(s)
Quality Control , Quality Control/policies , Quality Control , Argentina , Biological Variation, Population , Clinical Laboratory Services , Clinical Laboratory Techniques/standards , Total Quality ManagementABSTRACT
Objective To propose a practice model for implementing procedures employed for the verification of validated ex-amination procedures already used for at least 2 years in their laboratory,in agreement with the ISO 15189 requirement at the Section 5.5.1.2.Methods In order to identify the operative procedure to be used,approved documents were identified, together with the definition of performance characteristics to be evaluated for the different methods;the examination proce-dures used in laboratory were analyzed and checked for performance specifications reported by manufacturers.Then,opera-tive flow charts were identified to compare the laboratory performance characteristics with those declared by manufacturers. Results The choice of performance characteristics for verification was based on approved documents used as guidance,and the specific purpose tests undertaken,a consideration being made of:imprecision and trueness for quantitative methods;diag-nostic accuracy for qualitative methods;imprecision together with diagnostic accuracy for semi-quantitative methods.Conclu-sion The described approach,balancing technological possibilities,risks and costs and assuring the compliance of the funda-mental component of result accuracy,appears promising as an easily applicable and flexible procedure helping laboratories to comply with the ISO 15189 requirements.
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El valor de referencia del cambio (VRC) es el valor máximo que es permisible cambie el resultado de un analito entre dos mediciones sucesivas en un mismo paciente, sin que esta diferencia sea de relevancia clínica. Incluye critérios basados en la variabilidad biológica intraindividual (CVI) y la imprecisión analítica (CVA). La principal utilidad de los marcadores tumorales (MT) es el monitoreo de pacientes, resultando más apropiado informar el VRC que evaluar un resultado con su valor de referencia, como lo indica su bajo índice de individualidad. El objetivo fue evaluar la utilidad del VRC para detectar un cambio significativo entre resultados sucesivos en los principales MT. Se analizaron datos de sueros de controles de calidad de MT desde mayo de 2010 a febrero de 2014, se calculó el CVA%, y los datos de CVI % fueron obtenidos de bibliografía. Se calcularon los VRC para cada MT. Para los MT evaluados: AFP, CEA, CA125, CA15-3, CA19-9, PSA y tiroglobulina, los VRC fueron: 29.7, 32.3, 58.0, 16.3, 38.3, 42.7 y 34.2% respectivamente (p<0.05). Estos valores se compararon con datos bibliográficos. El VRC es un dato útil para el médico ya que colabora en la correcta interpretación de resultados seriados durante el seguimiento de pacientes, en la evaluación del tratamiento o en la estimación de recurrencias. Le permite saber si la diferencia encontrada entre dos valores consecutivos representa un cambio em el estado de salud del paciente. Nuestros VRC resultaron comparables con los de literatura
The reference change value (RCV) is the maximum allowable change between two consecutive results with no meaningful clinical relevance. It is analyzed within individual biological variability (CVI ) and analytical imprecision (CVA) criteria. For tumor markers (TM) monitoring is more appropriate to report RCV than reference interval due to their low individuality index. The aim of the study was to evaluate the usefulness of RCV to indicate a significant change between two consecutives TM results. Data from MT quality control serums (QC) were analyzed from May 2010 to February 2014, the imprecision was calculated as CVA% and CVI % data was obtained from literature. The RCV for each MT was calculated. The RCV for AFP, CEA, CA125, CA15-3, CA19-9, PSA and thyroglobulin were 29.7, 32.3, 58.0, 16.3, 38.3, 42.7 and 34.2% respectively (p < 0.05). These values were compared with literature data. The RCV is an appropriate tool for the clinicians and aids for the correct interpretation of results in the monitoring of patients, in treatment evaluation or estimation of recurrence. Physicians can determine whether the differences found between two successive values represent a change in the health status of the patient. The RCV calculated were comparable with those obtained in literature
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Humans , Reference Values , Mass Screening , LaboratoriesABSTRACT
Objective To learn how well these items of Hubei Province meet the quality standards of allowed imprecision. Methods Collected the indoor quality control data of median concentration levels from the laboratories which participated the project of interlaboratory comparisons of clinical chemistry indoor quality control data in Hubei Province.This paper was to analyze the variation coefficient of indoor quality control for 21 routine clinical chemistry examination items which were K,Na,Cl,TCa,P,GLu,Urea,UA,Cr,TP,Alb,TC,TG,ALT,AST,TBil,ALP,AMS,CK,LDH andγ-GT.The other objec-tive was to learn how well these items of Hubei Province meet the quality standards of allowed imprecision.Then took the 1/3 TEa,1/4 TEa,WS/T-403-2012 and minimum imprecision derived from biological variation as quality specification.And an-alyzed the percentage of laboratories in meeting the quality standards.Results The TG,ALT,CK and TBil in more than 50% of the participated laboratories could meet the quality standards of the 1/3 TEa,1/4 TEa,WS/T-403-2012 and the low-est appropriate imprecision derived from biological variation.The Cl and Cr in more than 50% of laboratories couldn’t meet the all above quality standards.The Na and TCa in all laboratories couldn’t meet the quality standards of best imprecision derived from biological variation.The evaluation criterion for qualified items setted was that the variation coefficient in more than 80% laboratories was less than the quality standard.Thus,the percentage of the items which meet the lowest quality standard of biological variation and the all 21 items was the most (66.7%).While the percentage of the items which met the quality standards of the WS/T403-2012 and the best biological variation was the least (14.3%).Conclusion In short,the values of indoor variation coefficient of the 21 items in laboratories which participated the project of interlaboratory compari-sons of clinical chemistry indoor quality control data generally met the requirements.But some items had a little higher de-gree of dispersion.The laboratories should set the appropriate imprecision levels based on the detection capability and quality standards and improve the quality of examination through continuous efforts.