User's Guide

Dexcom G6 System User Guide
290
Appendix F: Technical Information
Depending on the participant’s age, they participated in either 1, 2 or 3 clinic sessions
of varying duration.
• Adult subjects: two (2) or three (3) 12-hour clinic sessions
• Pediatric subjects 13-17 years of age: one (1) 12-hour clinic session
• Pediatric subjects 6-12 years of age: one (1) 6-hour clinic session
• Pediatric subjects 2-5 years of age: one (1) 4-hour clinic session (compared to
fingerstick blood glucose meter measurements only).
While using the G6 in the clinic, subjects had their blood glucose measured every 15
minutes with a laboratory reference method, the Yellow Springs Instrument 2300 STAT
Plus™ Glucose Analyzer. This instrument is referred to as the “YSI.” Readings from the
G6 were reported every 5 minutes and paired with YSI values in order to characterize
the accuracy of the G6’s glucose reading. No venous sampling was obtained for 14
pediatric subjects aged 2 to 5 years.
In Study 1, under close observation by the study investigator staff, the participant’s
glucose levels were deliberately manipulated per a protocol to raise or lower glucose to
achieve YSI glucose samples within target glucose bins. Glucose manipulations were
done to assess performance over the range that CGM measures glucose (40-400 mg/
dl). In Study 2, participant’s managed their glucose as they normally do; glucose was
not deliberately manipulated.
The data from these prospective clinical studies were further processed and analyzed
at Dexcom to assess performance of factory calibration.
Accuracy
Accuracy of the G6 is characterized by assessing its readings against blood glucose
values from YSI. Accuracy of the G6 was assessed with paired G6 readings to YSI
blood glucose values. For blood glucose values less than or equal to 70 mg/dL, the
absolute difference in mg/dL between the two glucose results was calculated. For
values greater than 70 mg/dL, the absolute difference (%) relative to the YSI values
was calculated. In addition, the mean absolute relative difference (MARD) shows the
average amount the sensor readings differ from the YSI glucose. The percentages of
total readings within 20 mg/dL or 20% (20/20%) are provided in Tables 1-A. The tables
are further categorized within CGM glucose ranges, within age groups, and sensor
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