Katzman Brooke M, Ness Karl M, Algeciras-Schimnich Alicia
Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, United States.
Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, United States.
Clin Biochem. 2017 Sep;50(13-14):768-771. doi: 10.1016/j.clinbiochem.2017.03.012. Epub 2017 Mar 18.
Verification of new reagent lots is a required laboratory task. The Clinical and Laboratory Standards Institute (CLSI) EP26-A guideline provides a lot-to-lot verification protocol to detect significant changes in test performance. The aim of this study was to compare the performance of EP26-A with our laboratory reagent lot verification protocol.
Prospective evaluations for two reagent lots each for thyroid stimulating hormone (TSH), thyroglobulin (Tg), thyroxine (T4), triiodothyronine (T3), free triiodothyronine (fT3), and thyroid peroxidase antibody (TPOAb) were performed. The laboratory's lot verification process included evaluation of 20 patient samples with the current and new lots and acceptability based on a predefined criteria. For EP26-A, method imprecision data and critical differences based on previously defined lot-to-lot consistency goals were used to define sample size requirements and rejection limits.
EP26-A required the following number of samples: 23 for TSH, 17 for Tg, 33 for T4, 31 for T3, 48 for fT3, and 1 for TPOAb. Our current protocol and EP26-A were in agreement in 9 of the 12 (75%) paired verifications. Of the 3 discrepant verifications, Tg and TSH reagent lots were rejected by EP26-A due to significant differences at medical decision points; whereas TPOAb was rejected by the current laboratory protocol.
The EP26-A protocol arrived at the same conclusions as our protocol in 75% of the evaluations and required more samples for 4 of the 6 analytes tested. Challenges associated with determining rejection limits and the need for increased sample sizes may be critical factors that limit the utility of EP26-A.
新试剂批次的验证是实验室的一项必要任务。临床和实验室标准协会（CLSI）的EP26 - A指南提供了一个批次间验证方案，以检测检测性能的显著变化。本研究的目的是比较EP26 - A与我们实验室试剂批次验证方案的性能。
对促甲状腺激素（TSH）、甲状腺球蛋白（Tg）、甲状腺素（T4）、三碘甲状腺原氨酸（T3）、游离三碘甲状腺原氨酸（fT3）和甲状腺过氧化物酶抗体（TPOAb）的两个试剂批次进行前瞻性评估。实验室的批次验证过程包括用当前批次和新批次评估20份患者样本，并根据预定义标准判断是否可接受。对于EP26 - A，基于先前定义的批次间一致性目标的方法不精密度数据和临界差异用于定义样本量要求和拒收限。
EP26 - A所需样本数量如下：TSH为23个，Tg为17个，T4为33个，T3为31个，fT3为48个，TPOAb为1个。在12组（75%）配对验证中，我们当前的方案与EP26 - A有9组一致。在3组不一致的验证中，由于在医学决策点存在显著差异，EP26 - A拒收了Tg和TSH试剂批次；而TPOAb被当前实验室方案拒收。
在75%的评估中，EP26 - A方案与我们的方案得出了相同的结论，并且在6种检测分析物中有4种需要更多的样本。与确定拒收限相关的挑战以及对增加样本量的需求可能是限制EP26 - A实用性的关键因素。
