Chakravarthy Srinivas Narasimhachar, Ramanathan Satish, S Smitha, Nallathambi Thirumalai, S Micheal
1Department of Laboratory Medicine, MIOT Hospitals, Chennai, India.
2Department of Clinical Biochemistry, MIOT Hospitals, No. 4/112, Mount Poonamallee Road, 4th Cross St, Sathya Nagar, Manapakkam, Chennai, Tamil Nadu 600089 India.
Indian J Clin Biochem. 2019 Jan;34(1):89-94. doi: 10.1007/s12291-017-0712-z. Epub 2017 Nov 15.
Verification of analytical performance of measurands becomes an essential requirement for the laboratories before proceeding to patients' samples testing. In our study we have verified the performance of HbA1C Immunoturbidimetric assay (VITROS 5600) against manufacturers' claims using CLSI EP15A3 Guidelines. We performed our study using two concentrations of Quality Control from Bio-Rad (Level 1 and Level 2). A precision verification study was carried out using five replicates of QC per day for five days following which imprecision estimates in form of Within Run (Repeatability) %CV and Within Lab %CV were calculated and compared against manufacturer's claims. Second part of our study included derivation of grand mean from the results of 25 replicates of QC used for precision verification. This was compared against the Target Value of the assigned QC obtained from the peer group mean of laboratories participating in interlaboratory QC program (unityTM Interlab-Bio-Rad) for %bias estimation. The findings of our precision study showed an acceptable Within Lab imprecision (%CV-0.6%), while the %CV -repeatability (%CV-0.54%) was greater than the manufacturer's claim (σR-0.5%). Hence upper verification limit for the manufacturer's claim (0.65%) was calculated against which the %CV Repeatability was compared and was found to be acceptable. The trueness verification showed that our grand mean (5.488%) was within the verification interval of the target value (5.462-5.497%) and hence the actual %bias was not statistically significant. Our study demonstrates that HbA1C immunoassay shows an acceptable performance consistent with the manufacturer's claims.
在对患者样本进行检测之前，验证被测量物的分析性能已成为实验室的一项基本要求。在我们的研究中，我们使用CLSI EP15A3指南，对照制造商的声明验证了HbA1C免疫比浊法（VITROS 5600）的性能。我们使用了两种浓度的伯乐公司的质量控制品（1级和2级）进行研究。进行了一项精密度验证研究，每天对质量控制品进行五次重复检测，共进行五天，之后计算批内（重复性）%CV和实验室内%CV形式的不精密度估计值，并与制造商的声明进行比较。我们研究的第二部分包括从用于精密度验证的25次质量控制品重复检测结果中得出总均值。将其与从参与实验室间质量控制计划（unityTM Interlab - 伯乐）的实验室的同组均值获得的指定质量控制品的目标值进行比较，以估计%偏差。我们精密度研究的结果显示实验室内不精密度可接受（%CV - 0.6%），而%CV重复性（%CV - 0.54%）大于制造商的声明（σR - 0.5%）。因此，计算了制造商声明的上限验证限（0.65%），并将%CV重复性与之比较，发现是可接受的。准确性验证表明，我们的总均值（5.488%）在目标值的验证区间内（5.462 - 5.497%），因此实际%偏差无统计学意义。我们的研究表明，HbA1C免疫测定法表现出与制造商声明一致的可接受性能。
