Plasma glucose measurement with the Yellow Springs Glucose 2300 STAT and the Olympus AU640

Background: Diabetes mellitus is an important diagnosis. New criteria have been defined for impaired glucose metabolism and, accordingly, there is a need for precise and accurate glucose analysis for the correct classification of patients. However, neither the World Health Organisation nor the National Service Framework for Diabetes in England and Wales deal with the associated analytical issues for plasma glucose. Aims/Methods: To compare two different methods for plasma glucose with respect to European and CLIA ’88 quality requirements. Results: Using several different graphical and statistical techniques, the YSI 2300 STAT was found to be 8.1–8.4% negatively biased for plasma glucose when compared with the Olympus AU640 method. Conclusions: Such a large bias would have a large impact on the detection of diabetes mellitus in clinical practice and therefore this method should not be used to make a definitive diagnosis. The bias probably results from the fact that the YSI 2300 STAT uses an aqueous based standard.