Journal of Radioanalytical and Nuclear Chemistry

, Volume 314, Issue 2, pp 737–742 | Cite as

Method validation and verification in liquid scintillation counting using the long-term uncertainty method (LTUM) on two decades of proficiency test data

  • F. Verrezen
  • M. Vasile
  • H. Loots
  • M. Bruggeman


Results from proficiency tests gathered over the past two decades by the laboratory for low level radioactivity measurements for liquid scintillation counting of 3H (184 results) and 14C (74 results) are used to verify the validated measurement methods used by the laboratory, in particular the estimated uncertainty budget of the method and its reproducibility and stability. A linear regression approach is used for the analysis of the results, described in the literature as the long term uncertainty in measurement method. The present study clearly indicates the advantages of using proficiency test results in identifying possible constant or proportional bias effects as well as the possibility to compare the laboratory performance with the performance of peer laboratories.


Liquid scintillation counting Measurement uncertainty Proficiency test Tritium Radio-carbon Validation Verification 



The authors of this paper would like to acknowledge all organizers of proficiency tests. Without their effort, the validation and verification of laboratory methods would be much harder.


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Copyright information

© Akadémiai Kiadó, Budapest, Hungary 2017

Authors and Affiliations

  • F. Verrezen
    • 1
  • M. Vasile
    • 1
  • H. Loots
    • 1
  • M. Bruggeman
    • 1
  1. 1.Low-level Radioactivity Measurements LaboratoryBelgian Nuclear Research Center, SCK-CENMolBelgium

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