Park Sang Hyuk, Park Chan-Jeoung, Kim Mi-Jeong, Choi Mi-Ok, Han Min-Young, Cho Young-Uk, Jang Seongsoo
Department of Laboratory Medicine, University of Ulsan College of Medicine and Asan Medical Center, Seoul, South Korea.
Am J Clin Pathol. 2014 Dec;142(6):777-87. doi: 10.1309/AJCPP0F9QXYOUJOG.
We developed and validated an interinstrument comparison method for automatic hematology analyzers based on the 99th percentile coefficient of variation (CV) cutoff of daily means and validated in both patient samples and quality control (QC) materials.
A total of 120 patient samples were obtained over 6 months. Data from the first 3 months were used to determine 99th percentile CV cutoff values, and data obtained in the last 3 months were used to calculate acceptable ranges and rejection rates. Identical analyses were also performed using QC materials. Two instrument comparisons were also performed, and the most appropriate allowable total error (ATE) values were determined.
The rejection rates based on the 99th percentile cutoff values were within 10.00% and 9.30% for the patient samples and QC materials, respectively. The acceptable ranges of QC materials based on the currently used method were wider than those calculated from the 99th percentile CV cutoff values in most items. In two-instrument comparisons, 34.8% of all comparisons failed, and 87.0% of failed comparisons were successful when 4 SD was applied as an ATE value instead of 3 SD.
The 99th percentile CV cutoff value-derived daily acceptable ranges can be used as a real-time interinstrument comparison method in both patient samples and QC materials. Applying 4 SD as an ATE value can significantly reduce unnecessarily followed recalibration in the leukocyte differential counts, reticulocytes, and mean corpuscular volume.
我们开发并验证了一种基于每日均值第99百分位数变异系数（CV）临界值的血液自动分析仪仪器间比较方法，并在患者样本和质量控制（QC）材料中进行了验证。
在6个月内共获取了120份患者样本。前3个月的数据用于确定第99百分位数CV临界值，后3个月获得的数据用于计算可接受范围和拒收率。使用QC材料也进行了相同的分析。还进行了两次仪器比较，并确定了最合适的允许总误差（ATE）值。
基于第99百分位数临界值的患者样本和QC材料的拒收率分别在10.00%和9.30%以内。在大多数项目中，基于当前使用方法的QC材料可接受范围比根据第99百分位数CV临界值计算的范围更宽。在双仪器比较中，所有比较中有34.8%失败，当将4标准差用作ATE值而非3标准差时，87.0%的失败比较成功。
基于第99百分位数CV临界值得出的每日可接受范围可作为患者样本和QC材料中的实时仪器间比较方法。将4标准差用作ATE值可显著减少白细胞分类计数、网织红细胞和平均红细胞体积中不必要的后续重新校准。
