the art of measurement: how to ensure accuracy in routine analyticalperformance, two case studies

Proficiency testing (pt) is a form of inter-laboratory comparison that aims to independentlyassess a laboratory's technical performance. during the pt process, laboratory staff test thedesignated item(s) without any specific considerations, and the announced results areevaluated using statistical techniques (iso 13528) [1]. among the available types of samplesfor testing, pts conducted with the consensus of participating laboratories are predominantlyfavored due to their cost-effectiveness and larger sample size. however, the potentialuncertainty and significant risks associated with the assigned value derived from theconsensus for evaluating participants' performance should not be overlooked, especiallywhen the participants are limited to a region. two domestic case studies concerning themeasurement of histamine in tuna fish and lead in dried tea revealed a notable discrepancybetween accuracy and precision, emphasizing the necessity of utilizing quality controlmaterials as test items for accurate detection.