Jump to ContentJump to Main Navigation

Clinical Chemistry and Laboratory Medicine (CCLM)

Published in Association with the European Federation of Clinical Chemistry and Laboratory Medicine (EFLM)

Editor-in-Chief: Plebani, Mario

Editorial Board Member: Gillery, Philippe / Kazmierczak, Steven / Lackner, Karl J. / Lippi, Giuseppe / Melichar, Bohuslav / Schlattmann, Peter / Whitfield, John B.

12 Issues per year

40% increased IMPACT FACTOR 2012: 3.009
Rank 5 out of 31 in category Medical Laboratory Technology in the 2012 Thomson Reuters Journal Citation Report/Science Edition

VolumeIssuePage

Issues

Bayesian analysis of an international ELISA comparability study

1 / Bernd Ebert1 / Jan Voigt1 / Monika Walzel1 / James E. Noble2 / Alex E. Knight2 / Clemens Elster1

1Physikalisch-Technische Bundesanstalt (PTB), Abbestr. 2-12, 10587 Berlin, Germany

2Analytical Science Group, National Physical Laboratory, Teddington, UK

Corresponding author: Katy Klauenberg, Physikalisch-Technische Bundesanstalt (PTB), Abbestr. 2-12, 10587 Berlin, Germany Phone: +49 30 3481 7614, Fax: +49 30 3481 69 7614

Citation Information: Clinical Chemistry and Laboratory Medicine. Volume 49, Issue 9, Pages 1459–1468, ISSN (Online) 1437-4331, ISSN (Print) 1434-6621, DOI: 10.1515/CCLM.2011.648, July 2011

Publication History

Received:
2011-01-24
Accepted:
2011-04-12
Published Online:
2011-07-05

Abstract

Background: Immunoassays are biochemical tests applied to measure even very small amounts of substance using the highly specific binding between an antibody and its antigen. They have a wide range of applications. The measurement however, might be associated with substantial uncertainty; this can have significant consequences for any diagnosis, or clinical decision. An international comparability study was thus performed to assess the sources of uncertainty involved in the estimation of a protein cytokine concentration using a fluorescent ELISA.

Methods: In contrast to the original publication for this international comparability study, we reanalyse the data using Bayesian inference. This provides a statistically coherent approach to estimate ELISA concentrations and their associated uncertainties.

Results: The Bayesian uncertainties of individual ELISAs and laboratory estimates are considerably larger than previously reported uncertainties. The average concentrations estimated here differ from the ones estimated by each study participant. In general, this leads to different conclusions about the study. In particular, the inter- and intra-laboratory consistency is increased, and repeatability problems occur for fewer laboratories.

Conclusions: Decisions which are based on plausible ranges of measurements (such as credible intervals), are generally superior to those solely based on point estimates (such as the mean). Reliable uncertainties are thus vital, and not only in metrology. In this paper, a general method is developed to derive concentration estimates and valid uncertainties for ELISAs. Guidance on applying this Bayesian method is provided and the importance of reliable uncertainties associated with ELISAs is underlined. The applicability and virtues of the presented method are demonstrated in the context of an international comparability study.

Keywords: Bayesian inference; CCQM; fluorescent ELISA; uncertainty

Comments (0)

Please log in or register to comment.
Users without a subscription are not able to see the full content. Please, subscribe or login to access all content.