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Troubleshooting Key Comparisons: A Survey of Design, Analysis, and Reporting of Results in Key Comparisons



Adriana Hornikova, William F. Guthrie


Key comparisons are international interlaboratory studies used to establish the degree of equivalence between national measurement standards. These studies, carried out by National Metrology Institutes, aer time-consuming, but necessary to facilitate international trade. Since the signing of the Mutual Recognition Arrangement (MRA) in 1999, approzimately one hundred and twenty key comparision in a wide range of metrological areas have been completed and have results posted in the Key Comparison Database (KCDB) maintained by International Bureau of Weights and Measures (BIPM) in France and in the International Comparisons Database (ICDB) maintained by the National Institute of Standards and Technology (NIST) in the U.S. As with may new standardized procedures, however, the translation of the guidelines for the conduct of key comparisons outlined in the MRA from theory to practice has not always been smooth or obvious. Different groups of metrologists working in different areas have interpreted the MRA in different ways. The practicalities of collecting data that support a specific measurement goal from laboratories all over the world has aslso had varying impact on the decisions made by the scientists who have planned and participated in key comparisons. Now, supported by a large set of completed comparisons from the KCDB and the ICDB, an opportunity has risen to study the methods that are being used to conduct key comparisons. This paper summarizes work currently completed key comparisons and offers recommendations for the design, analysis, and interpretation of future comparisons.
Proceedings Title
Proceedings| 2004
Conference Dates
August 8-12, 2004
Conference Location
Conference Title
Joint Statistical Meetings


experiment design, inter-laboratory studies, key comparison, MRA


Hornikova, A. and Guthrie, W. (2005), Troubleshooting Key Comparisons: A Survey of Design, Analysis, and Reporting of Results in Key Comparisons, Proceedings| 2004, Toronto, -1 (Accessed July 17, 2024)


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Created March 1, 2005, Updated February 17, 2017