Dexcom G5 User Manual page 320

Device What you see
BG Meter
Smart
Device:
In App
Receiver
Device What you see
Dexcom G5 Mobile System User Guide
Troubleshooting
Problem
Sensor
readings and
BG meter
glucose values
often don't
show the
same.
Problem
What you do
See Chapter 7.
Differences are not
uncommon.
Readings from different
body fluids reflect
different numbers:
Meter - from blood
Sensor - from interstitial
fluid
20/20 Rule
If the meter shows 80
or less, CGM should
read within ± 20 points.
If the meter shows 80
or above, the CGM
should read ± 20%.
Example: a 202 mg/dL
sensor reading and a
188 mg/dL glucose
meter value = a 7%
difference (this is still
considered accurate).
Outside of 20/20 rule:
Calibrate again.
What you do
320