The chronic injury glucose error grid: a tool to reduce diabetes complications

Abstract

Traditional glucose error grids provide error limits for glucose meters. These criteria help to assess the meter's suitability to prevent acute injury. We present a rationale for an error grid that provides a different set of error limits to help prevent chronic injury in diabetes. For example, glucose values in the no treatment zone of a traditional error grid could be harmful in diabetic retinopathy. The same method comparison data informs both the acute and chronic injury error grids. All of the data are used in an acute injury error grid, whereas only long-term biases populate a chronic injury error grid. These biases can be due to reagent lots and patient specific interferences. An example of a chronic injury glucose error grid is provided using simulated data.

Keywords: diabetes complications; error grid; long-term bias; surveillance.

Figure 1.

Glucose meter vs reference. Scatterplot of a glucose meter versus reference from a method comparison. The points at location P are likely to be interferences in a patient sample, whereas the deviation at point Q is likely a 1-time event.

Figure 2.

Glucose meter chronic error grid. The glucose bias calculated from regression falls within the A zone. The patient who had a large interference is in the C zone.