Calibration Overview - Dexcom G5 User Manual

Precaution
Enter the exact BG value displayed on your BG meter within five
Do:
minutes of a carefully performed fingerstick measurement.
Why: Entering the wrong BG values, or waiting more than five minutes
before entry, might affect sensor accuracy.
Consequences: You may miss a severe low or high glucose event.
Precaution
Only use fingerstick measurements from your BG meter for calibration.
Do:
Never use alternative site BG values such as blood from palms,
Don't:
forearms, etc.
Why: Alternative site BG values are different from a fingerstick BG value
and may not reflect most recent BG value.
Consequences: You may miss a severe low or high glucose event.

7.3 Calibration Overview

What Is a Calibration?
As you learned earlier, the sensor glucose readings come from measuring the
glucose fluids found between your cells (interstitial fluids). Although blood and
interstitial fluids are similar, sensor glucose readings can be different between
your fingerstick and your CGM. Calibration provides a comparison, or
measurement, between your meter's fingerstick measurement and the
sensor's glucose readings, allowing alignment between the sensor and meter.
Your BG meter "teaches" the sensor your glucose values through calibration.
Just like a clock can need adjusting—calibrations allow your CGM to adjust to
your body.
Why Is Calibrating Important?
Dexcom G5 Mobile System User Guide
Calibration
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