The GeoPT Proficiency Testing Scheme for Laboratories Routinely Analysing Silicate Rocks: A Review of the Operating Protocol and Proposals for its Modification. Issue 4 (2nd February 2015)

• Record Type: Journal Article
• Authors: Thompson, Michael; Webb, Peter C.; Potts, Philip J.
• Is Part Of: Geostandards and geoanalytical research. Volume 39:Issue 4(2015)
• Page Start: 433
• Page End: 442
• Publication Date: 2015-02-02
• Subjects: proficiency testing -- GeoPT -- laboratory performance -- quality assurance -- review -- z‐scores -- silicate rock analysis; essais d'aptitude -- GéoPT -- performance des laboratoires -- assurance qualité -- revue -- scores‐z -- analyse de roche silicatée; Analytical geochemistry -- Periodicals; Géochimie analytique -- Périodiques; 551.9
• DOI: 10.1111/j.1751-908X.2014.00343.x
• Languages: English
• ISSNs: 1639-4488

Abstract

Abstract : The Geo PT proficiency testing programme for geochemical laboratories has been operating for nearly 20 years. This review, based on an analysis of accumulated data and extensive experience, examines whether the protocol followed during this period continues to be appropriate. Possible changes that might be considered for future implementation are examined, in particular the procedures for calculating assigned values, target values, z ‐scores and the applicability of dual fitness‐for‐purpose criteria. We conclude that the existing protocol remains largely appropriate and effective, but propose that a single fitness‐for‐purpose criterion be adopted, with an option for laboratories to recalculate their z ‐scores if the criterion is inappropriate for their requirements.