Portable blood glucose meters (PBGMs) are frequently used because of their compact size, portability, relatively low cost, ability to provide blood glucose concentrations quickly, and usefulness for in-home monitoring of diabetic dogs and cats. This study evaluated the accuracy of 6 PBGMs by comparing results with those obtained with a reference chemistry analyzer. Six brands of PBGMs (AlphaTrak, Precision Xtra, Ascensia Elite XL, Ascensia Contour, Accu-Chek Advantage, OneTouch Ultra2) were evaluated, with a single meter of each brand used. For all 6 meters, the basic operation was the same: Blood was drawn into the reaction chamber of the test strip by capillary action, and blood glucose concentration was determined by means of an electrochemical or photometric method. Several dogs were identified for inclusion in the study on the basis of a potential for hyper- or hypoglycemia, given their suspected condition. Multiple blood samples were obtained at various times from some dogs included in the study to obtain samples with a wide range of blood glucose concentrations. Five of the dogs (5 blood samples) included in the study were considered healthy, 18 (113 blood samples) had diabetes mellitus, and 26 (40 blood samples) had various other medical conditions, including 5 dogs with insulinoma. Results suggested that there were substantial differences in the accuracy of currently available PBGMs. Overall, the results from the AlphaTrak and OneTouch meters were closest to results obtained with the reference analyzer and were associated with the lowest percentages of misclassification errors (hypoglycemic, euglycemic, or hyperglycemic). Blood glucose concentrations obtained with any newly purchased PBGM should therefore be compared with values obtained with a reference method to determine whether the meter tends to provide values that are low, high, or both. In addition, any animal identified by a PBGM as being hypoglycemic should be retested with a reference analyzer.

Commentary: Portable glucometers are a useful tool for in-home monitoring of diabetic patients; however, owners should be advised on the accuracy of various glucose meters before purchase and use. According to this study, the AlphaTrak and OneTouch meters had the lowest bias, but in general the bias tended to increase with higher plasma glucose measurements. Owners should still be educated about signs of hypo- and hyperglycemia and other complications of diabetes because therapy needs to be adjusted in conjunction with the clinical picture. Initial comparison with a plasma or serum reference method is recommended and should also be considered during patient recheck evaluations to ensure continued accuracy of the glucose meters.

Evaluation of six portable blood glucose meters for measuring blood glucose concentration in dogs. Cohen TA, Nelson RW, Kass PH, et al. JAVMA 235:276-280, 2009.