Accreditation and Quality Assurance

, Volume 13, Issue 2, pp 83–89

A practical procedure for assigning a reference value and uncertainty in the frame of an interlaboratory comparison

General Paper


A method is suggested for the calculation of a reference value and its uncertainty to be used in the frame of an interlaboratory comparison (ILC). It is assumed that the reference value of the measurand is determined independently from the ILC round. It is derived from a limited set of measurement results obtained from one or several expert laboratories. The procedure involves three stages: (1) check of the experimental data and possible corrections; (2) check of the consistency of data, and possibly increase of the uncertainties in order to attain internal consistency; (3) choice between fully, partially or un-weighted mean.


Interlaboratory comparison Reference value Mean Uncertainty 


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Copyright information

© Springer-Verlag 2007

Authors and Affiliations

  1. 1.European Commission, Joint Research CentreInstitute for Reference Materials and Measurements (IRMM)GeelBelgium

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