Proficiency Testing in Analytical Chemistry: 3 (Valid Analytical Measurement)

Product description Review "... an easy to read and concise introduction to the world of Proficiency Testing."-- "Accreditation and Quality Assurance, Vol 4, No 6/99, p265""...Definitive in outlining the spirit and practice of proficiency testing programs for all likely audiences in a clear and helpful manner."-- "The Analyst February 1998 Vol 123" From the Back Cover This book deals exclusively and comprehensively with the role of proficiency testing in the quality assurance of analytical data. It covers in detail proficiency testing schemes from the perspectives of scheme organisers, participant laboratories and the ultimate end-users of analytical data. A wide variety of topics are addressed including the organisation, effectiveness, applicability, and the costs and benefits of proficiency testing. Procedures for the evaluation and interpretation of laboratory proficiency, and the relation of proficiency testing to other quality assurance measures are also discussed. Proficiency Testing in Analytical Chemistry is an important addition to the literature on proficiency testing and is essential reading for practising analytical chemists and all organisations and individuals with an interest in the quality of analytical data. Excerpt. © Reprinted by permission. All rights reserved. Proficiency Testing in Analytical ChemistryBy Richard E. Lawn, Michael Thompson, Ronald F. WalkerThe Royal Society of ChemistryCopyright © 1997 LGC (Teddington)All rights reserved.ISBN: 978-0-85404-432-0ContentsChapter 1 Proficiency Testing in the Context of Valid Analytical Measurement, 1, Chapter 2 The Role of Proficiency Testing in Analytical Quality Assurance, 7, Chapter 3 Performance Scoring in Proficiency Testing – An Overview, 15, Chapter 4 Organisation of Proficiency Testing Schemes – General and Management Aspects, 24, Chapter 5 The Organisation of Proficiency Testing Schemes – Technical Aspects, 47, Chapter 6 Participation in Proficiency Testing Schemes by Analytical Laboratories, 73, Chapter 7 Proficiency Testing for End-users of Analytical Data, 81, Chapter 8 Proficiency Testing – The Future, 88, Glossary of Terms and Acronyms, 90, Appendix 1: Eurachem-UK Register of Proficiency Testing Schemes, 97, Appendix 2: Proficiency Testing Schemes Taking Part in the VAM, 100, Appendix 3: Examples of Performance Reports Issued by PT Scheme Organisers, 101, References, 107, Subject Index, 109, CHAPTER 1Proficiency Testing in the Context of Valid Analytical Measurement1.1 What is Proficiency Testing?A proficiency testing (PT) scheme comprises the regular distribution of test materials to participating laboratories for independent testing. The results are returned to the organiser of the scheme who makes an analysis of the results and reports them to all of the participants. The primary function of the scheme is. to assist the participants to detect shortcomings in their execution of the test procedures and apply suitable remedial measures to make up any deficiency. This is a particularly important function in analytical measurement, which is fraught with practical difficulties and prone to unsuspected errors. As well as this primary 'self-help' ethos, there is also an element of accreditation in many proficiency testing schemes. Accreditation agencies will normally expect candidate laboratories to participate satisfactorily in a proficiency test in areas of analytical measurement where one is available.Proficiency tests in analytical chemistry usually comply with a particular type, where the distributed materials are portions taken from an effectively homogeneous bulk material that resembles the normal test materials as closely as possible. The materials are distributed for analysis with choice of methods open, although participants should use their usual procedures. The estimated true value of the measurand is not revealed to the participants until after the collection of all of the results. The proficiency test therefore provides for the participant an independent check on the accuracy of the analytical result, albeit only at the time of the test. As the scheme is a regular event, it allows a laboratory to compare its results (i) with an external standard of quality, (ii) with the results of its peers and (iii) with its own past performance. Participation in a proficiency testing scheme therefore results in a much higher proportion of the participant laboratories reaching a satisfactory standard than would otherwise be the case. However, no consistent long-term improvements in performance will result unless the participation is in the context of an integrated quality assurance system within each laboratory.Care must be taken not to confuse proficiency testing with other types of interlaboratory study, that is those designed for validating analytical methods or certifying reference materials. The operational protocols for these three types of study are quite distinct (Section 4.3).1.2 Importance of Valid Analytical MeasurementsAc