Cook Andrea M, Moritz Andreas, Freeman Kathleen P, Bauer Natali
Department of Clinical Sciences, Clinical Pathophysiology and Clinical Pathology, Faculty of Veterinary Medicine, Justus-Liebig-University Gießen, Gießen, Germany.
IDEXX Laboratories, Ltd., Wetherby, UK.
Vet Clin Pathol. 2017 Jun;46(2):248-261. doi: 10.1111/vcp.12492. Epub 2017 May 3.
Information on quality requirements and objective evaluation of performance of veterinary point-of-care analyzers (POCAs) is scarce.
The study was aimed at assessing observed total errors (TE s) for veterinary hematology POCAs via meta-analysis and comparing TE to allowable total error (TE ) specifications based on experts' opinions.
The TE for POCAs (impedance and laser-based) was calculated based on data from instrument validation studies published between 2006 and 2013 as follows: TE = 2 × CV [%] + bias [%]. The CV was taken from published studies; the bias was estimated from the regression equation at 2 different concentration levels of measurands. To fulfill quality requirements, TE should be < TE . Measurands were considered as globally acceptable if > 60% of analyzers showed TE < TE .
Six studies evaluating 11 analyzers and 5 studies evaluating 5 analyzers were included for canine and feline hematology variables, respectively. For the CBC, TE was < 15% for canine and < 13% for feline measurands, except for HGB and platelet counts. Measurands of the CBC, excluding differential WBC and platelet counts, and HGB concentration were considered globally acceptable. For most of the cell types in the WBC differential count, TE was > TE (data from 3 analyzers).
This meta-analysis is considered a pilot study. Experts' requirements (TE < TE ) were fulfilled for most measurands except HGB (due to instrument-related bias for the ADVIA 2120) and platelet counts. Available data on the WBC differential count suggest an analytic bias, so nonstatistical quality control is recommended.
关于兽医即时检验分析仪（POCA）的质量要求和性能客观评估的信息匮乏。
本研究旨在通过荟萃分析评估兽医血液学POCA的观察总误差（TEs），并根据专家意见将TE与允许总误差（TEa）规范进行比较。
基于2006年至2013年发表的仪器验证研究数据，计算POCA（基于阻抗和激光的）的TE如下：TE = 2 × CV [%] + 偏差 [%]。CV取自已发表的研究；偏差通过在被测量物的2个不同浓度水平下的回归方程估算。为满足质量要求，TE应 < TEa。如果超过60%的分析仪显示TE < TEa，则被测量物被视为全球可接受。
分别纳入了评估11台分析仪的6项研究和评估5台分析仪的5项研究，用于犬猫血液学变量。对于全血细胞计数（CBC），除血红蛋白（HGB）和血小板计数外，犬的TE < 15%，猫的TE < 13%。CBC的被测量物，不包括白细胞分类计数和血小板计数以及HGB浓度，被视为全球可接受。对于白细胞分类计数中的大多数细胞类型，TE > TEa（来自3台分析仪的数据）。
本荟萃分析被视为一项初步研究。除HGB（由于ADVIA 2120的仪器相关偏差）和血小板计数外，大多数被测量物满足专家要求（TE < TEa）。关于白细胞分类计数的现有数据表明存在分析偏差，因此建议采用非统计质量控制。
