Welcome to the MARD, MARD World of Diabetes Care

FreeStyle Libre 3 goes below and beyond with 7.9% MARD, reaching a new level of glucose monitoring accuracy.

DIABETES CARE|Jun.28, 2022

Don't go pretending like you know what MARD is, or why it's important.

And don't worry. You're not alone.

Unless you're a physician, or your life involves continuous glucose monitoring (CGM), MARD — Mean Absolute Relative Difference — is not a term people slip into casual conversation. If you were hoping that just now reading what it stands for was going to help you figure it out, you have probably already realized that it really doesn't.

MARD is important because it is the standard way to measure CGM accuracy.

Like golf, the lower the number the better.

And, in the world of diabetes, that accuracy is critical.

Our FreeStyle Libre 3 was recently cleared by the U.S. Food and Drug Administration for use by people with diabetes 4 years and older with a MARD of 7.9% overall, the first CGM to demonstrate a sub-8% value, making it the most accurate 14-day CGM, with readings sent directly to a smartphone every minute.2,3

Keeping an Eye on a Very Small Target

Shridhara Alva knows something about the importance of precision and accuracy. As senior director of clinical affairs for Abbott’s diabetes care business, it was his clinical team that designed, executed and conducted the clinical study and data analysis for the study that was accepted by the FDA.

"Accuracy is extremely important in diabetes management," Alva said. "For anyone managing their diabetes with insulin, the more accurate the sensor they are using to track their glucose, the better it is.

"It was our job to demonstrate FreeStyle Libre 3's accuracy. It was important to us because taking care of one's diabetes is all about keeping the glucose levels within the recommended range, and the more accurate the glucose readings are, the more confident one is about management of their diabetes. If the sensor is inaccurate, misinformation could result in harm. That is what we are determined to avoid."

The introduction and development of CGMs has been a story of steady improvement in both the amount of information collected and its accuracy.

"Before sensors reached MARD values of about 10%, they could be used for general tracking and trending of glucose, but not to make medical decisions based only on the sensor’s readings," Alva said. (Note: All U.S. FreeStyle Libre sensors have a MARD of less than 10.0) "For those situations, you had to use blood glucose measurements (BGM)."

Optimizing Technology and Accuracy

Advancements in sensors and signal processing continued.

"Over time, the accuracy improved and the MARD values of less than 10% became possible, allowing the sensor data to be used for medical decision-making without BGM confirmation. Need for calibrating the sensor was eliminated with factory calibration of the individual sensor. Now we are in a place where we have the technological advantages of CGM, as well as increasingly accurate data. This puts us in a position where we can better correlate a person’s diet and exercise with the impact on their glucose readings," said Alva.

"Before CGM, it was hard to visualize the impact of eating say, a piece of fruit, unless one did a number of BGM measurements. Now, the CGM can note changes shortly after eating that fruit. In addition, the more accurate the readings, the better one can assess not only what caused the glucose fluctuation, but how much it fluctuated, which could then help the person moderate their diet in the future."

But there's more...

Other than the greatest accuracy, what else does this new system bring to the user?

  • It's the smallest and thinnest CGM sensor in the world.1,4 If you like the small MARD value, you will appreciate a sensor that is only the size of two stacked U.S. pennies.
  • It is even easier to use, with a one-piece, uncomplicated applicator to attach to the back of the upper arm.3
  • It has the most reliable Bluetooth integration with a range of up to 33 feet, 50% farther range than other CGMs.5

What more can one say about a sophisticated medical device that is small, accurate and can, according to Alva, "make a person’s life a lot easier?"

That to the person with diabetes, it may be the gate opening to a whole new MARD, MARD, World...


1 Data on File, Abbott Diabetes Care.
2Data on File, Abbott Diabetes Care. Comparison based on publicly available information.
3FreeStyle Libre 3 User's Manual
4Among patient-applied sensors.
5Based on the signal range in Dexcom G6 CGM User Guide and Medtronic Guardian Connect System User Guide.



Failure to use FreeStyle Libre 3 system as instructed in labeling may result in missing a severe low or high glucose event and/or making a treatment decision, resulting in injury. If glucose alarms and readings do not match symptoms or expectations, use a fingerstick value from a blood glucose meter for treatment decisions. Seek medical attention when appropriate or contact Abbott at 855-632-8658 or FreeStyleLibre.us for safety info.