Glucometers-need for external quality control

We performed a pilot accuracy study on glucometers from three sources: “Advantage” from Boehringer Mannheim (A), “Glucometer* 4” from Bayer (B) and “One Touch Basic” from Life Scan (C) and compared these results with the results on autoanalyzers-Dimension RxL (1) and Hitachi 704 (2). Each glucometer was tested with venous blood in duplicate, from three different groups of 20 patients each, at random, on three different days, in our outpatient phlebotomy section. The rest of the sample was collected into heparinized tubes & the plasma separated within 15 minutes of sample collection & analyzed on both the analyzers in duplicates. The data were analyzed for accuracy by tabulating the number and percentage of test values that vary from the analyzer (reference) method by 10% or less, by 10% to 20%, or greater than 20% and the results tabulated on the Accuracy Study Table. This being a pilot study and the numbers being small, it may be suggested from the Accuracy Study Table alone, that the results of glucose in whole blood done with glucometer (A) were comparable with that of plasma values without applying any factor; whereas the results with glucometers (B) & (C) need to be divided by 1.11 to be comparable with plasma results; statistically though, results with glucometer (C) were comparable with or without factor. Patients using glucometers need to be alerted about the variance in their glucose results when compared to laboratory results, more clearly by the respective companies in their product inserts. An external quality control material that is glucometer method specific is needed, so that the Clinical Biochemistry laboratory in any hospital setup can more effectively monitor the performance of the glucometers in the wards periodically.