The instability of commercial control materials in quality control of mean corpuscular volume

Abstract

BACKGROUND: Mean corpuscular volume (MCV) of stabilized whole blood used for quality control (QC) of hematology analyzers exhibits a tendency to increase during storage. The aim of this study is to evaluate the extent of biases over time with 3 most widely used control materials and to map out a strategy to overcome the data shift of MCV on daily QC practice. METHODS:QC results of TESTPoint tested by ADVIA 2120i, e-CHEK tested by XE 2100, and 6C Cell Control tested by DxH 800 were analyzed. RESULTS:MCV of all control materials showed a tendency to increase over time. By the fifth week, most of the materials showed biases larger than one standard deviation, with some exceeding a bias of four standard deviations. CONCLUSIONS:Laboratories should apply appropriate QC strategies in MCV tests by considering their individual quality and efficiency requirements.