This paper describes a metrological approach to evaluate the measurement capability of laboratories participating in a then Asia Pacific Laboratory Accreditation Cooperation [APLAC, now Asia Pacific Accreditation Cooperation] proficiency testing (PT) programme on mass fraction of acesulfame potassium and sucralose in cake mix flour. The programme was jointly organised by the Chemical Metrology Laboratory of the Health Sciences Authority, Singapore, and the Singapore Accreditation Council. Through the extensive APLAC network of accreditation bodies, 41 nominated laboratories from 32 economies registered, of which 40 laboratories submitted their results. Reference values of artificial sweeteners in the programme for performance evaluation were obtained from a high-accuracy liquid chromatography isotope dilution mass spectrometry (LC-IDMS) method. One of the unique features of this PT programme was the provision of pure substance certified reference materials (CRMs) of acesulfame potassium and sucralose to the participating laboratories as calibration standards to ensure comparability and metrological traceability of results. The participating laboratories’ performance, based on z-scores, were evaluated using the assigned reference value determined from IDMS. Five and one of the laboratories’ results would be incorrectly evaluated using consensus value calculated from the laboratories’ results for performance evaluation and using commercial standard as calibrant, respectively. This PT programme demonstrates the importance of the use of metrologically traceable reference values as the assigned values for appropriate evaluation of accuracy and reliable assessment. The provision of CRMs also heightened the testing laboratories’ awareness on the importance of using CRMs as calibrants for accurate measurements.

中文翻译：

---

一种基于准确度的能力验证程序，具有蛋糕粉中乙酰磺胺酸钾和三氯蔗糖质量分数的计量参考值

本文描述了一种计量方法，用于评估参与当时的亚太实验室认可合作组织 [APLAC，现为亚太认可合作组织] 能力测试 (PT) 计划的实验室测量能力，该计划针对蛋糕粉中乙酰磺胺酸钾和三氯蔗糖的质量分数。该计划由新加坡卫生科学局的化学计量实验室和新加坡认证委员会联合举办。通过广泛的 APLAC 认证机构网络，来自 32 个经济体的 41 个指定实验室进行了注册，其中 40 个实验室提交了结果。性能评估程序中人造甜味剂的参考值是通过高精度液相色谱同位素稀释质谱 (LC-IDMS) 方法获得的。该 PT 计划的独特之处之一是向参与实验室提供乙酰磺胺酸钾和三氯蔗糖的纯物质认证参考物质 (CRM) 作为校准标准，以确保结果的可比性和计量可追溯性。使用从 IDMS 确定的指定参考值，根据 z 分数评估参与实验室的性能。五个和一个实验室的结果将分别使用根据实验室性能评估结果计算的共识值和使用商业标准作为校准物进行错误评估。该 PT 程序证明了使用可计量溯源的参考值作为适当评估准确度和可靠评估的指定值的重要性。