The Norwegian Quality Improvement of Primary Care Laboratories (Noklus), Haraldsplass Deaconess Hospital, Bergen, Norway;
The Norwegian Quality Improvement of Primary Care Laboratories (Noklus), Haraldsplass Deaconess Hospital, Bergen, Norway; Department of Public Health and Primary Health Care, Faculty of Medicine and Dentistry, University of Bergen, Bergen, Norway.
Clin Chem. 2016 May;62(5):708-15. doi: 10.1373/clinchem.2015.247585. Epub 2016 Mar 15.
Providers of external quality assurance (EQA)/proficiency testing schemes have traditionally focused on evaluation of measurement procedures and participant performance and little attention has been given to reagent lot variation. The aim of the present study was to show the importance of reagent lot registration and evaluation in EQA schemes.
Results from the Noklus (Norwegian Quality Improvement of Primary Care Laboratories) urine albumin/creatinine ratio (ACR) and prothrombin time international normalized ratio (INR) point-of-care EQA schemes from 2009-2015 were used as examples in this study.
The between-participant CV for Afinion ACR increased from 6%-7% to 11% in 3 consecutive surveys. This increase was caused by differences between albumin reagent lots that were also observed when fresh urine samples were used. For the INR scheme, the CoaguChek INR results increased with the production date of the reagent lots, with reagent lot medians increasing from 2.0 to 2.5 INR and from 2.7 to 3.3 INR (from the oldest to the newest reagent lot) for 2 control levels, respectively. These differences in lot medians were not observed when native patient samples were used.
Presenting results from different reagent lots in EQA feedback reports can give helpful information to the participants that may explain their deviant EQA results. Information regarding whether the reagent lot differences found in the schemes can affect patient samples is important and should be communicated to the participants as well as to the manufacturers. EQA providers should consider registering and evaluating results from reagent lots.
外部质量保证（EQA）/能力验证计划的提供者传统上侧重于评估测量程序和参与者的表现，而很少关注试剂批次的变化。本研究的目的是展示 EQA 计划中试剂批次注册和评估的重要性。
本研究使用了 2009 年至 2015 年期间来自 Noklus（挪威初级保健实验室质量改进）的尿液白蛋白/肌酐比值（ACR）和凝血酶原时间国际标准化比值（INR）即时 EQA 计划的结果作为示例。
Afinion ACR 的参与者间 CV 在连续 3 次调查中从 6%-7%增加到 11%。这种增加是由于白蛋白试剂批次之间的差异引起的，当使用新鲜尿液样本时也观察到了这种差异。对于 INR 方案，CoaguChek INR 结果随着试剂批次的生产日期而增加，试剂批次中位数从 2.0 到 2.5 INR 和从 2.7 到 3.3 INR（从最旧到最新的试剂批次）分别增加对于 2 个控制水平。当使用本地患者样本时，没有观察到这些批次中位数的差异。
在 EQA 反馈报告中呈现来自不同试剂批次的结果可以为参与者提供有帮助的信息，这些信息可能解释了他们异常的 EQA 结果。有关方案中发现的试剂批次差异是否会影响患者样本的信息很重要，也应向参与者以及制造商传达。EQA 提供者应考虑注册和评估试剂批次的结果。
