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What event usually prompts you to calibrate your CGM? Please select all that apply.
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I usually calibrate 1-2 times during the first 24 hours of new sensor wear as, for me, the cgm readings tend to be lower than actual bg by fingerstick.
Generally, I don’t calibrate my CGM. I wear a Dexcom G7, which I trust. So, I said, “Accuracy reasons (i.e., CGM says I’m low, but I don’t feel like I am) ,” and “Not trusting the glucose reading on the CGM .” But, not so much the latter.
I calibrate first thing in the morning, before lunch and before bed. I find this keeps my CGM accurate all the time instead of waiting until there’s an issue.
I use a Dexcom G7 and find that if my calibration number is more than 20% or so different, it is not accepted.
Once it even prompted the sensor session to end/forced me to replace the sensor.
Has anyone else seen this?
I use a G6 and usually calibrate it once a day when my BG has been stable for several hours. I find this makes the G6 a bit more accurate. I also find the G6 lags a bit with hypoglycemia, so if I’m symptomatic I check with a Contour meter.
I haven’t calibrated my Dexcom since the G5, I think.
When I change my infusion set, my sensor and my Dexcom G6.
I always do finger stick checks when I change my sensor. I use the Dexcom G7. I usually find it to be off and so I put in the calibration number. I keep doing the checks over the first day or so, until I am satisfied that the readings are close enough.
Should I not be doing this??
For me the first 3 hrs the CGM is super low, but usually pretty close within 12 hrs. But yes, I check frequently too until I’m confident in the new sensor.
I switched to the Dexcom CGM 7 in January and have had to call them many items about inaccurate readings especially during the 1st day. They have told me NOT to calibrate for the first 24 hours. I confess that although I used Dexcom for over 10 years I’m changing to the Eversense CGM next month just to compare accuracy. Hopefully time will tell!
In my experience providers need to be educated on how to educate patients on CGM use. Since first using a CGM I’ve seen 3 endos, a half dozen PCPs and a CDE and none reviewed best practices for making treatment decisions with a CGM or reasonable expectations for accuracy.
unable to calibrate a Libre3
Surprised this isn’t on the list, but it’s usually because the CGM doesn’t match my trusted finger stick meters.
All measurement equipment should be calibrated on a regular basis. For me, CGM should be calibrated in the first couple hours, again half way though session (5days), and again near the end of the session (8 days). And if course, if readings seem off! I find that G7 is often reporting well below my “lows” once I’m past day 6, screaming 50 if I’m 70…it’s frustrating.
Regarding this question, my experience with blood test stirips is that they can be VERY inaccurate. I once did three finger blood tests in a row, and came out with results 50, 120, 180 (these are not the exact numbers, because it was years ago). After that, I switched blood test brands, to Contour Next. Personally, I feel that my CGM is just as accurate as my blood test strips, perhaps more accurate. Generally, I trust my CGM numbers.
As instructed by my Endo. Sensor technician, Diabetes educator and 46 years of experience using a Pump and 13 years using a CGM System, me.
In the last 2 years, I can specifically remember 1x that I did not need to calibrate when I begin a new sensor with my Dexcom. It’s always off, sometimes reading higher, sometimes lower; always.
Rarely calibrate my CGM.
I was dx’d about 25 yrs before getting a CGM (G4) and it took a while to trust it to the point of letting go of finger sticks, when the G6 came along. But I never quite cut the tether. My habit is to test first thing in the morning as a kind of sanity-check, and I’ll calibrate if it’s >20 pts off. I also habitually test when the sensor first comes out of warm up (I’m still on G6) because that’s almost always significantly high vs finger-stick. People say not to calibrate at that point but I’ve found it works better for me to just go ahead and do that, especially as I’m now using an AID pump (T-slim with CIQ) so it’s a lot more critical.
When it’s giving me a reading that doesn’t match how I feel, reading low and my blood sugar using my Contour Next meter is perfect. This happens almost every time I put on a new Dexcom CGM 7 my readings are way off. Dexcom says “low” but fingerstick says my blood sugar is 90-120; because my husband, daughter and son all follow me I end up texting everyone what my true readings are so they don’t worry. Then after the 1st day I verify CGM accuracy daily and calibrating if readings are off by more than 20%.
If I feel that my CGM is inaccurate, I will compare to a finger stick and only calibrate if it is fairly far off.
I never calibrate during the first day. The first 12 hours are usually way off so I just let the CGM settle in
I calibrate when I change my CGM- every 10 days in addition to the times mentioned in the multiple choice question.
I calibrate daily
I am unable to calibrate my CGM. Freestyle Libre
The Freestyle Libre CGMs are factory calibrate, patients can’t calibrate them. I do a blood check whenever my CGM reading doesn’t match how I feel, but my CGM is accurate 90+% of the time. Love the Libre 3!
“Trust” must always govern period. If we cannot, or do not trust the CGM numbers, either they give us dead accurate numbers or we are just plain dead…. and the CGM numbers are plain garbage. Why do we need to “prove”/verify the CGM numbers are true. A paradox I cannot get around.
I calibrate when my meter is more than 10-15% off. I check every morning and whenever my reading does not match what I expect my bg to be given what I have eaten or what I have been doing.
I found my G7 to be very accurate so I’ve stopped finger sticking. I’ve only been in CGM 4 months so that may change, but my last A1C was 6.1 with 83% in range, so I’m happy not finger sticking. Got enough needles in my body.
When test strip is greater than plus or minus 40 the Dexcom 7, I calibrate.
After starting a new cgm sensor. Also fasting every morning.