Linsinger Thomas P J, Auclair Guy, Deprez Liesbet
Joint Research Centre, European Commission, Retieseweg 111, 2440, Geel, Belgium.
Anal Bioanal Chem. 2025 May;417(12):2617-2627. doi: 10.1007/s00216-025-05751-0. Epub 2025 Feb 4.
The commutability of three certified reference materials for Cd, Cr, Hg, Ni, Pb and Tl in blood was evaluated for the combination of digestion ICP-MS with dilution ICP-MS or dilution GFAAS using the difference in bias approach. Maximum non-commutability bias (MANCB) was derived from the median of the tolerance limits set by six proficiency testing (PT) providers. The evaluation showed that this criteria are too strict and that either unfeasible high number of measurements or a larger MANCB is required to demonstrate commutability. The effect of increasing the MANCB on the maximum tolerable measurement uncertainty was found small to moderate demonstrating the commutability of the materials when used as a calibrator. Also the inclusion of the uncertainty of non-commutability into the measurement uncertainty resulted in only small increases of the measurement uncertainty, demonstrating the suitability of the materials for trueness control and method validation. The bias of the three CRMs was for most elements within the 99% confidence limits of the bias of the patient samples, demonstrating the suitability of the materials for statistical quality control.
采用偏差差异法，对三种血液中镉、铬、汞、镍、铅和铊的有证标准物质在消解电感耦合等离子体质谱法与稀释电感耦合等离子体质谱法或稀释石墨炉原子吸收光谱法联用中的互换性进行了评估。最大不可互换偏差（MANCB）源自六个能力验证（PT）提供者设定的容许限中位数。评估表明，该标准过于严格，要证明互换性，要么需要进行数量多得不可行的测量，要么需要更大的MANCB。发现增加MANCB对最大可容忍测量不确定度的影响较小到中等，这表明这些物质用作校准物时具有互换性。此外，将不可互换性的不确定度纳入测量不确定度中，只会使测量不确定度有小幅增加，这表明这些物质适用于真实性控制和方法验证。三种有证标准物质的偏差，对于大多数元素而言，都在患者样本偏差的99%置信限内，这表明这些物质适用于统计质量控制。
