Mean absolute relative difference
Continuous glucose monitor accuracy measure
From Wikipedia, the free encyclopedia
Mean Absolute Relative Difference (MARD) is a standard metric used to evaluate the accuracy of continuous glucose monitoring systems,[1] which gives the average amount a CGM sensor reading varies from the actual blood glucose.[2] It is calculated by taking the average of the absolute relative differences between the glucose readings reported by the CGM system and corresponding reference measurements, typically obtained through laboratory analysis or blood glucose meters.[3] A lower MARD value indicates greater accuracy, and it is commonly used in clinical research and regulatory evaluations to compare the performance of different CGM devices. It is also of note that MARD percentages can vary by person, even while using the same device.[1]
MARD by device
| Device | MARD | Release year | Notes |
|---|---|---|---|
| Dexcom STS | 20.3% | 2006 | [4] |
| Dexcom Seven | 17% | 2007 | [5] |
| Dexcom Seven Plus | 16% | 2010 | [5] |
| Dexcom G4 Platinum | 13.9% | 2012 | [6] |
| Dexcom G5 Mobile | 9% | 2015 | [7] |
| Dexcom G6 | 9% | 2018 | [8] |
| Dexcom G7 | 8.2% | 2022 | [9] |
| Dexcom G7 15-Day | 8% | 2024 | [10] |
| FreeStyle Libre 1 | 13.7% | 2014 | [11] |
| FreeStyle Libre 2 | 9.3% | 2020 | [12] |
| FreeStyle Libre 3 | 7.8% | 2022 | [13] |