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Uncertainty in measurement and total error: different roads to the same quality destination?
Ian Farrance1, Tony Badrick2, Robert Frenkel3
1Discipline of Laboratory Medicine, School of Health and Biomedical Sciences, RMIT University, Bundoora, Victoria 3083, Australia.
Clinical Chemistry and Laboratory Medicine
|June 28, 2018
Summary
This study clarifies the ongoing debate on laboratory performance assessment, contrasting measurement uncertainty (MU) with total error (TE). It offers an alternative perspective on the relationship between ISO15189, MU, and the Guide to the Expression of Uncertainty in Measurement (GUM).
Area of Science:
- Clinical Chemistry
- Laboratory Medicine
- Metrology
Background:
- The assessment of laboratory performance involves a continuing debate between measurement uncertainty (MU) and total error (TE).
- A recent summary by the EFLM's Task and Finish Group on Total Error (TFG-TE) has been influential.
- Despite strong support for TE in many laboratories, some arguments require further examination.
Purpose of the Study:
- To present an alternative view on the key issues in the MU vs. TE debate for laboratory performance assessment.
- To clarify the relationship between ISO15189, uncertainty in measurement, and the Guide to the Expression of Uncertainty in Measurement (GUM).
- To address potentially confusing statements promoting TE methods for uncertainty assessment.
Main Methods:
- Critical review of arguments presented by the TFG-TE.
- Analysis of the application and interpretation of ISO15189 and GUM in laboratory performance assessment.
- Presentation of an alternative perspective on measurement uncertainty and total error.
Main Results:
- The study identifies potentially confusing statements regarding ISO15189 and GUM in the context of TE.
- It highlights the need for a clearer understanding of how MU and TE apply to laboratory performance.
- An alternative viewpoint on the relationship between these standards and methods is proposed.
Conclusions:
- The current promotion of TE methods for uncertainty assessment may be based on a misinterpretation of relevant standards.
- A re-evaluation of the roles of MU and TE in laboratory quality management is necessary.
- Clarification is needed regarding the integration of ISO15189 and GUM principles for robust laboratory performance evaluation.
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