Accreditation and Quality Assurance

, Volume 18, Issue 5, pp 367–372 | Cite as

A new profile likelihood confidence interval for the mean probability of detection in collaborative studies of binary test methods

  • Steffen UhligEmail author
  • Sven Krügener
  • Petra Gowik
General Paper


A confidence interval for the probability of detection across laboratories (LPOD) for qualitative methods, described in the AOAC INTERNATIONAL guidelines for validation of microbiological methods for food and environmental surfaces, is considered. It is demonstrated that under certain conditions, the observed confidence of this confidence interval can be rather low, so that statistical minimum requirements are not fulfilled. A new profile likelihood confidence interval based on a latent random laboratory effect approach is proposed. Observed confidence levels for this confidence interval demonstrate its applicability already for a small number of laboratories.


POD Collaborative study Confidence interval Qualitative test Validation Latent random effect Observed confidence Coverage 



The authors wish to thank the anonymous reviewers for their valuable comments and suggestions to improve the quality of the paper.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2013

Authors and Affiliations

  1. 1.QuoDataFreisingGermany
  2. 2.QuoDataDresdenGermany
  3. 3.Federal Office for Consumer Protection and Food SafetyBerlinGermany

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