Araştırma Çıktıları

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Author: search.filters.author.Bartlett, William A.Has files: Yes

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    Biological Variation of Cardiac Troponins in Health and Disease: A Systematic Review and Meta-analysis
    (OXFORD UNIV PRESS INC, 2021-01-01) Diaz-Garzon, Jorge; Fernandez-Calle, Pilar; Sandberg, Sverre; Ozcurumez, Mustafa; Bartlett, William A.; Coskun, Abdurrahman; Carobene, Anna; Perich, Carmen; Simon, Margarita; Marques, Fernando; Boned, Beatriz; Gonzalez-Lao, Elisabet; Braga, Federica; Aarsand, Aasne K.; Chem, European Federation Clinical; Database, Task Grp Biol Variation
    BACKGROUND: Many studies have assessed the biological variation (BV) of cardiac-specific troponins (cTn), reporting widely varying within-subject BV (CVI) estimates. The aim of this study was to provide metaanalysis-derived BV estimates for troponin I (cTnI) and troponin T (cTnT) for different sampling intervals and states of health. METHODS: Relevant studies were identified by a systematic literature search. Studies were classified according to their methodological quality by the Biological Variation Data Critical Appraisal Checklist (BIVAC). Meta-analyses of BIVAC-compliant studies were performed after stratification by cTn isoform, exclusion of results below the limit of detection, states of health, and sampling interval to deliver reference change values (RCV), index of individuality (II) and analytical performance specifications (APS) for these settings. RESULTS: Sixteen and 15 studies were identified for cTnI and cTnT, respectively, out of which 6 received a BIVAC grade A. Five studies had applied contemporary cTnI assays, but none contemporary cTnT. High-sensitivity (hs-) cTnI and cTnT delivered similar estimates in all settings. Long-term CVI estimates (15.1
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    A checklist for critical appraisal of studies of biological variation
    (2014-01-01) Bartlett, William A.; Braga, Federica; Carobene, Anna; Coskun, Abdurrahman; Prusa, Richard; Fernandez-Calle, Pilar; Roraas, Thomas; Jonker, Neils; Sandberg, Sverre; Grp, Biol Variation Working; Chem, European Federation Clinical
    Data on biological variation are used for many purposes in laboratory medicine but concern exists over the validity of the data reported in some studies. A critical appraisal checklist has been produced by a working group established by the European Federation of Clinical Chemistry and Laboratory Medicine (EFLM) to enable standardised assessment of existing and future publications of biological variation data. The checklist identifies key elements to be reported in studies to enable safe accurate and effective transport of biological variation data sets across healthcare systems. The checklist is mapped to the domains of a minimum data set required to enable this process.
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    Harmonization initiatives in the generation, reporting and application of biological variation data
    (2018-01-01) Aarsand, Aasne K.; Roraas, Thomas; Bartlett, William A.; Coskun, Abdurrahman; Carobene, Anna; Fernandez-Calle, Pilar; Jonker, Niels; Diaz-Garzon, Jorge; Braga, Federica; Sandberg, Sverre; Chem, European Federation Clinical
    Biological variation (BV) data have many applications in laboratory medicine. However, concern has been raised that some LW estimates in use today may be irrelevant or of unacceptable quality. A number of initiatives have been launched by the European Federation of Clinical Chemistry and Laboratory Medicine (EFLM) and other parties to deliver a more harmonized practice in the generation, reporting and application of BV data. Resulting from a necessary focus upon the veracity of historical BV studies, critical appraisal and meta-analysis of published BV studies is possible through application of the Biological Variation Data Critical Appraisal Checklist (BIVAC), published in 2017. The BIVAC compliant large-scale European Biological Variation Study delivers updated high-quality BV data for a wide range of measurands. Other significant developments include the publication of a Medical Subject Heading term for BV and recommendations for common terminology for reporting of BV data. In the near future, global BV estimates derived from meta-analysis of BIVAC appraised publications will be accessible in a Biological Variation Database at the EFLM website. The availability of these high-quality data, which have many applications that impact on the quality and interpretation of clinical laboratory results, will afford improved patient care.
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    Within-subject and between-subject biological variation estimates of 21 hematological parameters in 30 healthy subjects
    (WALTER DE GRUYTER GMBH, 2018-01-01) Coskun, Abdurrahman; Carobene, Anna; Kilercik, Meltem; Serteser, Mustafa; Sandberg, Sverre; Aarsand, Aasne K.; Fernandez-Calle, Pilar; Jonker, Niels; Bartlett, William A.; Diaz-Garzon, Jorge; Huet, Sibel; Kiziltas, Cansu; Dalgakiran, Ilayda; Ugur, Esra; Unsal, Ibrahim; Varia, E.F.L.M. Working Grp Biological
    Background: The complete blood count (CBC) is used to evaluate health status in the contexts of various clinical situations such as anemia, infection, inflammation, trauma, malignancies, etc. To ensure safe clinical application of the CBC, reliable biological variation (BV) data are required. The study aim was to define the BVs of CBC parameters employing a strict protocol. Methods: Blood samples, drawn from 30 healthy subjects (17 females, 13 males) once weekly for 10 weeks, were analyzed using a Sysmex XN 3000 instrument. The data were assessed for normality, trends, outliers and variance homogeneity prior to coefficient of variation (CV)-analysis of variance (ANOVA). Sex-stratified within-subject (CVI) and between-subjects (CVG) BV estimates were determined for 21 CBC parameters. Results: For leukocyte parameters, with the exception of lymphocytes and basophils, significant differences were found between female/male CVI estimates. The mean values of all erythrocyte-, reticulocyte- and platelet parameters differed significantly between the sexes, except for mean corpuscular hemoglobin concentration, mean corpuscular volume and platelet numbers. Most CVI and CVG estimates appear to be lower than those previously published. Conclusions: Our study, based on a rigorous protocol, provides updated and more stringent BV estimates for CBC parameters. Sex stratification of data is necessary when exploring the significance of changes in consecutive results and when setting analytical performance specifications.