1 Department of Chemistry, Technical University of Denmark2 Analytical Chemistry, Department of Chemistry, Technical University of Denmark3 Department of Chemistry, Technical University of Denmark
Contemporary research in quality assurance indicates that large uncertainties observed in interlaboratory comparisons to a large extent originate from a lack of competence of laboratory staff. This explanation is challenged by the present article for which six technologies and multiple series of experiments were investigated with respect to uncertainty of measurement and treatment of outliers. It was found that long-term precision was poor in comparison to short-term precision. The ratio of predicted uncertainty to observed uncertainty was determined as significantly above 1, and it was suggested that a correction factor is needed for the predicted uncertainty. This indicates that statistical control could be obtained only by treating many independent series of experiments and using pooled calibrations in the method validation. Retention of outliers in calculation of contents and calculation of uncertainties of certified reference materials (CRMs) gave results that differed significantly from those in the certificates of the CRMs. (C) 2014 Elsevier B.V. All rights reserved.
Trends in Analytical Chemistry, 2014, Vol 60, p. 16-24
certified reference material; consensus science; interlaboratory comparison; pooled calibration; quality assurance development; statistical control; Primates Mammalia Vertebrata Chordata Animalia (Animals, Chordates, Humans, Mammals, Primates, Vertebrates) - Hominidae  human common; 00532, General biology - Miscellaneous; 04500, Mathematical biology and statistical methods; Computational Biology; mathematical method mathematical and computer techniques; General Life Studies; Mathematical Biology; CHEMISTRY,; ANALYTICAL-CHEMISTRY; METHOD VALIDATION; ENVIRONMENTAL-MEDICINE; POOLED CALIBRATIONS; OUTLIER DETECTION; METROLOGY; LABORATORIES; UNCERTAINTY; PRINCIPLES; RECOMMENDATIONS; Certified reference material; Chemical analysis; Competence; Consensus science; Interlaboratory comparison; Method validation; Outlier; Precision; Quality assurance; Uncertainty