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Comparison of value-assigned CRMs and PT materials: experimental design and data evaluation



David L. Duewer, Hugo H. Gasca-Aragon, Katrice A. Lippa, Blaza Toman


This document provides the “tedious mathematical details” for OAWG Track B Key Comparisons – that is, this document presents and discusses the statistical approaches involved in the design of Track B studies and analysis of the resulting data. This document is not required reading for an adequate appreciation of the conclusions drawn from the CCQM K79 “Comparison of value-assigned CRMs and PT materials: ethanol in aqueous matrix” and CCQM K80 “Comparison of value-assigned CRMs and PT materials: creatinine in human serum” studies. This document is a necessary adjunct to the CCQM K79 and/or –K80 reports for anyone seeking to understand and/or critique the design and analysis of these studies and it is recommended reading for anyone who wishes to propose or coordinate another OAWG Track B study.


CCQM (Consultative Committee on the Quantity of Matter – Chemistry), CRM (Certified Reference Material), GDR (Generalized Distance Regression), KC (Key Comparison), KCRF (Key Comparison Reference Function), OAWG (Organic Analysis Working Group)


Duewer, D. , Gasca-Aragon, H. , Lippa, K. and Toman, B. (2012), Comparison of value-assigned CRMs and PT materials: experimental design and data evaluation, BIPM, [online], (Accessed May 22, 2024)


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Created August 21, 2012, Updated September 28, 2020