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4.4.2 How to do a good calibration
No.
Do
Not to do
1
Calibrate when CGM reading is within your target range, if
possible close to your BG target. And so is your goal to keep your
sensor glucose in the target range as much as possible.
Do not over-calibrate: calibrate two or three times per day,
no more – unless, in the event of such: CGMS readings
are more than 20% off the BG test value. CGMS
algorithms may become unstable when calibrated too
often in a day.
2
Only calibrate when your CGMS arrow is stable '→'.
Do not always assume that glucose meter is right and
CGMS is wrong. When in doubt, test two or three times.
CGMS has been averaging glucose meter errors (only
guaranteed to +/- 20%) for several days – it could well be
closer to the true value overtime than glucose meter.
3
You should be ready to calibrate more frequently than usual, if
need be, during the first 3 days.
Avoid calibration when CGMS value arrow shows rise '↑',
rapid rise '↑↑', decrease “↓', rapid decrease '↓↓'.
4
It’s better to validate that your true BG is stable. When you are
not sure if your BG is stable, do fingerstick twice within an
interval of 5 minutes. If the second reading is similar to the first
one, then do a calibration using the latest BG test.
N/A
