Clarke Error Grid

The Error Grid Analysis (short: EGA including error grid analysis ) is used to evaluate the clinical accuracy of blood glucose readings compared to a reference value.

It was, inter alia, ( Charlottesville Department of Pediatrics, University of Virginia Medical School ) developed by W. Clarke in the 1970s. Originally it was used to determine the clinical accuracy of patient opinion on the current blood glucose value compared to the value that the patient had received with his device for SMBG ( Self Monitoring of Blood Glucose, SMBG ). Later, this analysis has been increasingly used to compare the clinical accuracy of the determined with the instruments for SMBG values ​​with a reference value. A description of the EGA appeared in the journal " Diabetes Care " in 1987. Finally, the Error Grid analysis to one of the " gold standard " for determining the accuracy of blood glucose meters.

The Grid (grid, grid ) classifies the measured blood glucose values ​​of the assessed measuring device and the reference device in five regions.

• Region A includes all the values ​​which have a maximum deviation of 20 % from the reference value.
• Region B has all the values ​​that indeed more than 20% from the reference value vary, but do not lead to a decision have a faulty impact on the therapy of the patient.
• Region C, here are those results that have unnecessary decisions result.
• Region D shows all values ​​that indicate a potentially dangerous error in the detection of hypo - or hyperglycemia and in the
• Region E are all results that would lead to confusion in the treatment of hypoglycemia or hyperglycemia and vice versa.