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A statistical procedure for the assessment of bias in analytical methods using conditional probabilities

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Abstract

A new approach is described for the simultaneous treatment of bias and imprecision in clinical chemistry. The approach makes use of the general law of conditional probabilities. The result is a density distribution of the measurand that incorporates both imprecision and bias and avoids the contentious linear combination of these quantities as a ‘total error’. This leads naturally to a figure-of-merit in proficiency testing or method comparison that has intuitive visual appeal. We also discuss an established figure-of-merit in proficiency testing, namely the E n number.

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Acknowledgements

R. B. Frenkel acknowledges his former affiliation with the National Measurement Institute, Australia.

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Authors and Affiliations

  1. 96 Shirley Rd, Roseville, NSW, 2069, Australia

    Robert B. Frenkel

  2. Discipline of Laboratory Medicine, School of Health and Biomedical Sciences, RMIT University, Bundoora, VIC, 3083, Australia

    Ian Farrance

  3. National Measurement Institute Australia, Bradfield Rd, West Lindfield, NSW, 2070, Australia

    Robert B. Frenkel

Authors
  1. Robert B. Frenkel
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  2. Ian Farrance
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Correspondence to Robert B. Frenkel.

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Frenkel, R.B., Farrance, I. A statistical procedure for the assessment of bias in analytical methods using conditional probabilities. Accred Qual Assur 22, 265–273 (2017). https://doi.org/10.1007/s00769-017-1274-8

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  • DOI: https://doi.org/10.1007/s00769-017-1274-8

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