Every analyst takes analysis context on their decision on the analysis result. If a residue of a pesticide never authorised in a crop production site is identified, extra confirmation of the finding is performed. In clinical analysis, if a specific…
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Applying the uncertainty propagation law (i.e. the well-known Taylor Series Method) to measurements involving a complex mathematical relation between various input quantities is difficult. The link below directs you to a video that briefly explains the principles and the implementation…
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Many chemical parameters are determined as the difference, d, between two measured values, designated as larger (g) and lower (w) inputs, (d = g – w; where g > w) determined from independent measurements such as: Magnesium Hardness (mg/L of CaC03) = Total Hardness –…
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Eurachem, together with CITAC, have published a guide on how to assess and report the performance of qualitative analyses. This guide describes some of the tools that can be used to check if qualitative analyses have fit for purpose uncertainty….
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Talanta paper on the top-down evaluation of the measurement uncertainty from correlated validation data following regulated validation design. Link: https://www.sciencedirect.com/science/article/abs/pii/S0039914020306779 #Metrology #Uncertainty #Validation #AnalyticalChemistry #Crossvalidation #Correlation Research Novelty: This work presents and cross-validates a novel top-down measurement uncertainty evaluation…
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Free share link: https://authors.elsevier.com/a/1bFkQ,ashxm80 (Until 7 August 2020) The assessment of long-term trends in river water composition is hampered by river composition heterogeneity, and sampling and sample analysis uncertainty. This work describes a novel methodology for the reliable detection of…
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The paper “Monte Carlo Bottom-up Evaluation of Global Instrumental Quantification Uncertainty: Flexible and user-friendly computational tool” makes bottom-up uncertainty evaluations easy! (DOI doi.org/10.1016/j.chemosphere.2020.127285). This research presents a novel and flexible tool for the Monte Carlo simulation of global instrumental quantifications uncertainty…
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The new requirement of the ISO/IEC 17025 standard for discussing with the customers the impact of the measurement uncertainty in the reliability of conformity decisions and for subsequently using it in conformity assessments is not just another novelty of the…
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Detecting single and paired outliers in replicate signals of calibration standards can be useful. Please find below a link for the spreadsheet. Outliers are identified by cell colours. The test’s confidence level can be selected in W column. Single…
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According to VIM3 [1], a method is: a “generic description of a logical organization of operations used in a measurement” (Entry 2.5) (e.g. standard addition method or gas-chromatography) …therefore, methods cannot be validated because are too general. The detailed description…
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A measurement result is usually expressed as a (“measured quantity value” ± “measurement uncertainty”). The measured quantity value aims at estimating the “true” quantity value of a measurand (VIM3: Entry 2.10). On the other hand, the measurement uncertainty is evaluated…
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You can find attached a MS-Excel file that automatically reports result, with uncertainty, with correct significant digits number. Link: Post2019_09_21_MSExcel_SignificantFiguresSelector_VerA posts/ricardo-silva-758a5362_excel-digits-uncertainty-activity-6581229039590215680-RcVS
Many important decisions are based on qualitative results (i.e. examinations) suggesting a well-known quote from Lord Kelvin is somehow incomplete…
The programme of the Eurachem workshop “Uncertainty from sampling and analysis for accredited laboratories” (Berlin, 19-20 November 2019) is available in website of the event: Programme.