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Introduction: Quality Control Management (QCM) in clinical laboratories is crucial for ensuring reliable results in analytical measurements, with biological variation being a key factor. The study focuses on assessing the analytical performance of the Reverse Transcription Polymerase Chain Reaction (RT-PCR) system for Human Immunodeficiency Virus (HIV), Hepatitis B (HBV), and Hepatitis C (HCV). Five models proposed between 1999 and 2014 offer different approaches to evaluating analytical quality, with Model 2 based on biological variation and Model 5 considering the current state of the art. The study evaluates the RT-PCR system's analytical performance through Internal Quality Control (IQC) and External Quality Control (EQC). Materials and Methods: The Laboratório Central de Saúde Pública do Estado do Ceará (LACEN-CE) conducted daily IQC using commercial kits, and EQC was performed through proficiency testing rounds. Random error, systematic error, and total error were determined for each analyte. Results: Analytical performance, assessed through CV and random error, met specifications, with HIV and HBV classified as "desirable" and "optimal." EQC results indicated low systematic error, contributing to total errors considered clinically insignificant. Conclusion: The study highlights the challenge of defining analytical specifications without sufficient biological variability data. Model 5 is deemed the most suitable. The analytical performance of the RT-PCR system for HIV, HBV, and HCV at LACEN-CE demonstrated satisfactory, emphasizing the importance of continuous quality control in molecular biology methodologies.
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Objetivo: Optimizar el control interno de calidad de RT-PCR en tiempo real para detección cualitativa de SARS-CoV-2, utilizando los valores Cq de controles negativos y positivos. Material y método: Estudio prospectivo-longitudinal. La muestra estuvo constituida por 143 valores Cq para los controles negativos de alicuotado y extracción, así como para el control positivo. Se analizó la distribución normal de los valores Cq mediante la prueba de Anderson-Darling (AD) y se aplicaron pruebas de aleatoriedad. Se calculó límites de control a partir de 51 valores Cq, para luego, mediante gráficas de control, monitorizar 92 valores Cq obtenidos desde noviembre del 2020 hasta marzo del 2021. Se evaluó aceptación de lote e índices Cpk como indicadores de optimización. Los cálculos se hicieron con el programa Minitab. Resultados: Se aceptaron los lotes de valores Cq y se obtuvieron índices Cpk superiores a 1.33 para los tres tipos de control. Discusión: No existen estudios publicados que apliquen control estadístico de calidad a la detección cualitativa de SARS-CoV-2. Conclusiones: Es posible utilizar los valores Cq de los controles para optimizar el control interno de calidad de RT-PCR en tiempo real para detección cualitativa de SARS-CoV-2, como si se tratara de una técnica de tipo cuantitativo.
Objective: To optimize the internal quality control of real-time RT-PCR for the qualitative detection of SARS-CoV-2, using the Cq values of negative and positive controls. Material and method : Prospective-longitudinal study. The sample consisted of 143 Cq values for the negative aliquot and extraction controls, as well as for the positive control. The normal distribution of Cq values was analyzed using the Anderson-Darling (AD) test and randomness tests were applied. Control limits were calculated from 51 Cq values, and then, using control charts, to monitor 92 Cq values obtained from November 2020 to March 2021. Lot acceptance and Cpk indices were evaluated as optimization indicators. The calculations were made with the Minitab program. Results: The batches of Cq values were accepted and Cpk indices higher than 1.33 were obtained for the three types of control. Discussion : There are no published studies that apply statistical quality control to the qualitative detection of SARS-CoV-2. Conclusions : It is possible to use the Cq values of the controls to optimize the internal quality control of real-time RT-PCR for qualitative detection of SARS-CoV-2, as if it were a quantitative technique.
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OBJECTIVE: KPIs have been employed for internal quality control (IQC) in ART. However, clinical KPIs (C-KPIs) such as age, AMH and number of oocytes collected are never added to laboratory KPIs (L-KPIs), such as fertilization rate and morphological quality of the embryos for analysis, even though the final endpoint is the evaluation of clinical pregnancy rates. This paper analyzed if a KPIs-score strategy with clinical and laboratorial parameters could be used to establish benchmarks for IQC in ART cycles. METHODS: In this prospective cohort study, 280 patients (36.4±4.3years) underwent ART. The total KPIs-score was obtained by the analysis of age, AMH (AMH Gen II ELISA/pre-mixing modified, Beckman Coulter Inc.), number of metaphase-II oocytes, fertilization rates and morphological quality of the embryonic lot. RESULTS: The total KPIs-score (C-KPIs+L-KPIs) was correlated with the presence or absence of clinical pregnancy. The relationship between the C-KPIs and L-KPIs scores was analyzed to establish quality standards, to increase the performance of clinical and laboratorial processes in ART. The logistic regression model (LRM), with respect to pregnancy and total KPIs-score (280 patients/102 clinical pregnancies), yielded an odds ratio of 1.24 (95%CI = 1.16-1.32). There was also a significant difference (p<0.0001) with respect to the total KPIs-score mean value between the group of patients with clinical pregnancies (total KPIs-score=20.4±3.7) and the group without clinical pregnancies (total KPIs-score=15.9±5). Clinical pregnancy probabilities (CPP) can be obtained using the LRM (prediction key) with the total KPIs-score as a predictor variable. The mean C-KPIs and L-KPIs scores obtained in the pregnancy group were 11.9±2.9 and 8.5±1.7, respectively. Routinely, in all cases where the C-KPIs score was ≥9, after the procedure, the L-KPIs score obtained was ≤6, a revision of the laboratory procedure was performed to assess quality standards. CONCLUSION: This total KPIs-score could set up benchmarks for clinical pregnancy. Moreover, IQC can use C-KPIs and L-KPIs scores to detect problems in the clinical-laboratorial interface.
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Benchmarking/normas , Laboratórios/normas , Indicadores de Qualidade em Assistência à Saúde/normas , Técnicas de Reprodução Assistida/normas , Adulto , Feminino , Humanos , Modelos Estatísticos , Gravidez , Taxa de Gravidez , Estudos Prospectivos , Controle de QualidadeRESUMO
Quality control procedures are indispensable to ensure the reliability of the results provided by laboratories responsible for serological screening in blood banks. International recommendations on systems of quality management classify as a top component the inclusion of two types of control: (a) internal quality control (IQC) and (b) external quality control (EQC). In EQC it is essential to have, at least, a monthly frequency of laboratory assessment. On the other hand, IQC involves the daily use of low-reactivity control sera, which should be systematically added in all run, carried out in the laboratory for each parameter. Through the IQC analysis some variations in the criteria of run acceptance and rejection may be revealed, but it is of paramount importance to ensure the previous definition of these criteria and even more importantly, the adherence to them; and that corresponds to the validation of analytical runs of each test. Since 2010 this has been, for instance, the experience of the PNCQ*, developing external quality control programmes on serology for blood banks. These programmes use samples of lyophilized sera well-characterized for the reactivity related to the parameters used for the serological screening of blood donors. The programmes have used blind panels of six samples for monthly assessments. In the last 50 assessments, which involved 68 blood banks in Brazil, a significant number of instances of non-compliance were observed in all monthly assessments. These results provide strong support to the recommendation of systematic monthly assessments. (*) National Quality Control Programme (PNCQ).
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En el proceso de verificación de métodos se obtienen datos del desempeño del sistema de medición en las condiciones de trabajo del laboratorio; luego esto es cotejado con las especificaciones brindadas por el fabricante de reactivos y con los requerimientos de calidad disponibles de distintas fuentes. Los objetivos del presente trabajo fueron aplicar protocolos de evaluación de métodos publicados en guías internacionales (CLSI, Clinical Laboratory Standard Institute) para verificar el correcto rendimiento de las metodologías evaluadas y diseñar e implementar una estrategia de control de calidad interno (CCI) que permita evaluar la estabilidad del sistema de medición en el tiempo. Se evaluaron glucosa, creatinina y láctico deshidrogenasa (LDH); sobre las metodologías para la valoración de los mismos se realizaron los ensayos correspondientes a la verificación de precisión y veracidad, linealidad, límite de detección, comparación de equipos y establecimiento de valores de referencia de acuerdo con lo establecido en las guías CLSI EP15-A2, EP6-A, EP17-A, EP9-A2, C28-A2, respectivamente. En todos los ensayos realizados se cumplieron con las especificaciones estipuladas por el fabricante para cada analito, como así también con los requerimientos de calidad elegidos para el error total permitido. Además, se determinó el punto operativo y se especificaron las reglas de CCI adecuadas para el seguimiento del desempeño de estas metodologías. Con los resultados obtenidos se construyó una matriz de calidad para hacer el seguimiento mensual de los parámetros evaluados. Aplicando procedimientos de verificación de métodos se demostró la aceptabilidad de los parámetros analíticos evaluados. La verificación de los métodos permite diseñar y aplicar una estrategia de CCI para evaluar la estabilidad analítica de los sistemas de medición en el tiempo, dentro de un marco de seguridad analítica exigido para métodos acreditados.
The process of method verification (MV) generates data about the performance of a measuring system in current laboratory working conditions; later, the information obtained is compared to the specifications issued by the assay manufacturer and International Regulating Organizations. The objectives of this study were: 1) to apply evaluation protocols established by international guidelines (CLSI, Clinical Laboratory Standards Institute) to verify the correct performance of the methodologies under analysis; 2) to design and implement a strategy of internal quality control (IQC) that allows evaluating the stability of the measuring system in time. Glucose, creatinine and lactate deshidrogenase were subject to analysis. Verification of precision, trueness, linearity detection limit, instrument comparison and reference values were performed under the provisions of CLSI EP-15A2, EP6A, EP17-A, EP9-A2 and C28-A2 guidelines, respectively. For every assay, the procedures indicated by the manufacturer were respected, as well as the quality requirements chosen for total allowed error. An operative point was obtained and adequate ICQ rules for monitoring the performance of those methodologies were established. With the results obtained, a quality matrix was built for a monthly follow-up of the evaluated parameters. The acceptability of the evaluated analytical parameters was proved by the application of MV procedures. Furthermore, the MV enabled to design and implementation of an ICQ strategy to test the analytical stability of the measuring systems, in the analytical safety environment required for accredited methods.
No processo de verificação de métodos são obtidos dados do desempenho do sistema de medição nas condições de trabalho do laboratório; depois isto é comparado com as especificações oferecidas pelo fabricante de reagentes de laboratório e com os requerimentos de qualidade disponíveis em diversas fontes. Os objetivos do presente trabalho foram aplicar protocolos de avaliação de métodos publicados em guias internacionais (CLSI, Clínical Laboratory Standard Institute) para verificar o correto rendimento das metodologias avaliadas e desenhar e implementar uma estratégia de controle de qualidade interno (CCI) que permita avaliar a estabilidade do sistema de medição no tempo. Foram avaliadas glicose, creatinina e desidrogenase lática (LDH); sobre as metodologias para a avaliação dos mesmos foram realizados os ensaios correspondentes à verificação de precisão e veracidade, linearidade, limite de detecção, comparação de equipamentos e estabelecimento de valores de referência conforme o estabelecido nos guias CLSI EP15-A2, EP6-A, EP17-A, EP9-A2, C28-A2, respectivamente. Em todos os ensaios realizados foram cumpridas as especificações estabelecidas pelo fabricante para cada analito, bem como com os requerimentos de qualidade selecionados para o erro total permitido. Além disso, foi possível determinar o ponto operacional e especificar as regras do CCI adequadas para o acompanhamento do desempenho destas metodologias. Com os resultados obtidos se construiu uma matriz de qualidade para fazer o acompanhamento mensal dos parâmetros avaliados. Aplicando procedimentos de verificação de métodos foi demonstrada a aceitabilidade dos parâmetros analíticos avaliados. A verificação dos métodos permite desenhar e aplicar uma estratégia de CCI para avaliar a estabilidade analítica dos sistemas de medição no tempo, dentro de um quadro de segurança analítica exigido para métodos com credenciamento.