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Accreditation and Quality Assurance: Journal for Quality, Comparability and Reliability in Chemical Measurement (v.3, #4)
Qualification and validation of software and computer systems in laboratories by L. Huber (pp. 140-144).
Installation and operational qualification are important steps in the overall validation and qualification process for software and computer systems. This article guides users of such systems step by step through the installation and operational qualification procedures. It provides guidelines on what should be tested and documented during installation prior to routine use. The author also presents procedures for the qualification of software using chromatographic data systems and a network server for central archiving as examples.
Keywords: Key words Validation; Qualification; Computers; Software; Analytical; Laboratories
Uncertainty – statistical approach, 1/f noise and chaos by P. Serapinas (pp. 145-149).
Some general reasons for poor applicability of the statistical approach based on approximation of normal data distribution to interlaboratory test results and analytical measurements at high data dispersion are considered. They include a symmetry of the concentration scale, low-frequency noise, and nonlinear phenomena in atomization processes and chemical reactions. The relationship of 1/f noise and nonlinear phenomena to uncertainty balance, experimental verification of the assigned uncertainty value, ruggedness tests and statistical data distribution are briefly discussed.
Keywords: Key words Uncertainty; Interlaboratory test; Noise; Data distribution; Nonlinear phenomena
Detection limits and quantitation limits in the view of international harmonization and the consequences for analytical laboratories by Rüdiger Kaus (pp. 150-154).
In the literature and in daily work there exist many different models to describe detection limits and quantitation limits in the chemical measurement process (CMP). It is still an open question whether the evaluation of detection and quantitation limits should be an one-off process carried out during the validation of a CMP, or whether it should be a continuous process. Because of these reasons many laboratories have difficulties to interprete such values. It is necessary that the official standardization bodies should do some efforts in the international harmonization of the special standards concerning detection and quantitation limits.
Keywords: Key words Chemical measurement process; Capability of detection; Detection limit; Quantitation limit; International harmonization
Validation of the uncertainty evaluation for the determination of metals in solid samples by atomic spectrometry by R. J. N. Bettencourt da Silva; M. Filomena G. F. C. Camões; João Seabra e Barros (pp. 155-160).
Every analytical result should be expressed with some indication of its quality. The uncertainty as defined by Eurachem ("parameter associated with the result of a measurement that characterises the dispersion of the values that could reasonably be attributed to the, . . ., quantity subjected to measurement") is a good tool to accomplish this goal in quantitative analysis. Eurachem has produced a guide to the estimation of the uncertainty attached to an analytical result. Indeed, the estimation of the total uncertainty by using uncertainty propagation laws is components-dependent. The estimation of some of those components is based on subjective criteria. The identification of the uncertainty sources and of their importance, for the same method, can vary from analyst to analyst. It is important to develop tools which will support each choice and approximation. In this work, the comparison of an estimated uncertainty with an experimentally assessed one, through a variance test, is performed. This approach is applied to the determination by atomic absorption of manganese in digested samples of lettuce leaves. The total uncertainty estimation is calculated assuming 100% digestion efficiency with negligible uncertainty. This assumption was tested.
Keywords: Key words Uncertainty; Validation; Quality control; Solid samples; Atomic spectrometry
Information on the Activity of the IUPAC Interdivisional Working Party on Harmonization of Quality Assurance Schemes for Analytical Laboratories
by A. Fajgelj; Michael Parkany (pp. 163-165).
International Symposium on Chemical measurement: world-wide inter- laboratory comparisons
by A. Squirrell; Ron Walker (pp. 165-168).
Third European Conference on Quality Management in Clinical Laboratories: "QUALITY (R)EVOLUTION IN CLINICAL LABORATORIES", 30–31 October 1997, Antwerp, Belgium
by J. C. Libeer; H. M. J. Goldschmidt (pp. 168-169).
Glossary of Analytical Terms (X)*
by Elizabeth Prichard; Heiner Albus; Bernd Neidhart; Wolfhard Wegscheider (pp. 171-173).