Diabetes Bites Newsletter

Accuracy findings of a study that evaluated performance of G6, Dexcom’s factory-calibrated CGM system specified for 10-day wear.

The study included 262 participants, age 6 and up with type 1 diabetes or insulin-managed type 2 diabetes. The sensor was worn for one 10 day session on the abdomen (or for those age 6-17 on the abdomen or upper butt).  Calibration of the system was done once daily, but the analysis of sensor data was done solely on the raw sensor data independent of self-monitored blood glucose values used for the calibration. 

Participants attended clinic sessions for comparison of CGM vs fingerstick data on days 1, 4-5, 7 and day 10. 

CGM performance was evaluated for the proportion of CGM values within +/- 20% of the glucose values >100mg/dl or within +/-20mg/dl of glucose values < or equal to 100md/dl (%20/20), the analogous %15/15, and the MARD (mean absolute relative difference) between CGM and reference glucose value.

%20/20 and MARD

92.3% and 10%

MARD by day of use

%20/20 on day 1 (88.6%) and day 10 (90.6%)

Matched pair comparison – adult/youth

%20/20 = 92.4% and 91.9%

MARD = 9.9% and 10.1%

Alert detection reliability (prediction of “urgent low soon” within 20 min)

85% accurate within 30 min before BG<70mg/dl

Sensor life

10 day survival rate = 87%

Read the original article here: https://www.liebertpub.com/doi/10.1089/dia.2018.0150