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Can the usual validation standard series for quantitative methods, ISO 5725, be also applied for qualitative methods?

  • Steffen UhligEmail author
  • Ludwig Niewöhner
  • Petra Gowik
General Paper

Abstract

Repeatability standard deviation, laboratory standard deviation, and reproducibility standard deviation for quantitative methods according to ISO 5725 series were recently proposed to estimate the precision of qualitative measurements, giving a presence/absence response. In this paper, it is shown that for qualitative methods, the reproducibility standard deviation across laboratories does not reflect the performance of the method as suggested. It is demonstrated that the benefit of the respective laboratory standard deviation is very limited. Alternative performance measures are introduced which are based on another approach also directly linked to ISO 5725. Thereby, meaningful information about the precision of qualitative test methods can be achieved.

Keywords

Qualitative methods Quantitative methods ISO 5725 Reproducibility standard deviation Repeatability standard deviation Laboratory standard deviation Probability of detection response curve 

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Copyright information

© Springer-Verlag 2011

Authors and Affiliations

  1. 1.quo dataMunich-FreisingGermany
  2. 2.Federal Criminal Police OfficeWiesbadenGermany
  3. 3.Federal Office of Consumer Protection and Food SafetyBerlinGermany

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