[Comparison of the accuracy and precision of 7 reflectometers in self-control of blood glucose].

7 types of reflectance meters (Hypocount GA and MXB, Glucometer II and M, Petita B and B II, Reflolux II) were tested for accuracy and for within-run precision. To test the accuracy blood sugar was measured in 30 venous blood samples in the blood glucose ranges from 30 to 70, 71 to 180 and 181 to 300 mg/dl resp. on 4 instruments of each meter-type and by the hexokinase method as a reference method. With Hypocount MXB and Glucometer II great differences between correlation coefficients within the 4 instruments occurred. In the low blood glucose range all meters correlated best with the hexokinase method whereas poorer results were obtained in the low and the high glucose range. As regards the mean percental deviation, Reflolux II correlated closely with the reference method in the blood glucose range from 30 to 70 mg/dl, Hypocount MXB in the range from 71 to 180 mg/dl and Petita B in the range from 181-300 mg/dl. The greatest differences were found with both types of Hypocount- and Petita-meters in low blood sugar levels. With none of the tested meters a linear correlation with the hexokinase method was observed over the whole blood glucose range. Coefficients of variation for within-run precision ranged from 1.9% (Reflolux II) to 8.1% (Hypocount GA) depending on blood glucose concentration.