Sarah Howard
Sarah Howard has worked in the diabetes research field ever since she was diagnosed with T1D while in college in May 2013. Since then, she has worked for various diabetes organizations, focusing on research, advocacy, and community-building efforts for people with T1D and their loved ones. Sarah is currently the Senior Marketing Manager at T1D Exchange.
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If you use a CGM that does not require regular calibrations, on average, how often do you choose to calibrate your CGM with a blood glucose meter reading? Cancel reply
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I calibrate at least once, sometimes up to 3 times per session. Some sites just have more error or drift throughout the session (my belly especially).
It just depends. Every once in a while I will get a cranky Sensor and have to calibrate 2-4 times during the 10 day session. Most the time I don’t need to calibrate.
I agree with Carol Meares, it definitely depends on the G6 sensor. I rarely calibrate, but if I’m suddenly getting extreme low alarms that have little relation to the food I’ve eaten and the amount of insulin I’ve taken in response, I’ll check with my meter and calibrate to correct if more than an acceptable difference. I called Dexcom last week to replace a sensor for that reason. It doesn’t happen that often.
I agree with Carol Meares,. I can go months with the G6 never calibrating once. Then a cranky one, usually with an erratic communication issues, seems to require 4,5, or 6 calibrations. 🫤
I use the G6 and usually calibrate it 3-4 during it’s 10 day lifespan.
Usually I have to calibrate my G6 toward the end of the 10 days – it starts going all wonky on me and telling me I’m super low, which I’m not. That’s when I know it’s almost time to put a new sensor on.
Libre2 can’t be calibrated. If you’ve got a lousy sensor, you’re stuck. If it’s way off, I’ll use a new one and call Libre and they’re usually pretty good about replacing them.
Same👆
Wow, as a scientist who’s worked with instrumentation for over 25 years, I’m alarmed you can’t calibrate the Libre! How is that even approved for such a critically important value?
Usually when I get a very low or high CGM reading in order to double check. I know CGM
readings can be quite different at those extremes
Dexcom seems to be more accurate for me than it used to be. Used to be way off first day but now right on target with a finger stick
Dexcom G6 user. I calibrate a few times each session because most often my BG is lower than the CGM indicates, which is a problem on the low end. I try to calibrate it up so the CIQ on my Tandem can catch my lows correctly.
Should have been some different answer choices like “it just depends on the sensor”. Some sensors are cranky and some go just fine. Hard to coreectly answer this question.
Multiple times a day, almost every time I use my glucometer. I find the Dexcom readings useful as indications, but the glucometer readings much more reliable as guides to action, although Dexcom considers the differences between the two as being within their 30% acceptable differential == something I don’t feel so comfortable with.
I use Dexcom G6 and rarely calibrate. I only calibrate if the sensor seems way off or when I am either too high or too low and the meter tells me I’m way, way off. And usually that means I need a new sensor!
I am very interested to see the answers to this question! After 30 years of diabetes, I just can’t *not* check in with a finger stick daily. I usually do it first thing in the morning. Otherwise I wouldn’t feel confident that the numbers I’m seeing are accurate. Perhaps I will get over this with time but CGMs are still “new” compared to blood glucose meters in my mind.
What CGM… DOESN’T….require calibrations? None of them should be trusted 100%.
do you mean corroborate or calibrate? Libre has no means of changing the readings to match those of a glucose monitor device. But it can be compared.
I try to Calibrate at least every 4-6 Months – G6
I use the Dexcom G6. After start up it is usually way off, typically high. So I will always calibrate on Day 1. I rarely calibrate afterwards
I wasn’t calibrating my Dexcom at all but found that I got highs that were way off so I started checking unexpected highs. Turns out they were often wrong when compared to finger check.
Weird and disappointing to g but still like my Dexcom, just know I sometimes need to verify.
I CK THE DAY I CHANGE THE SENSOR, AND CHANG MY PUMP INFUSION SITE OCC if I have had a steroid injection, usually at bedtime.
I use G6. Usually will do a random bg check on day 1 or 2. Will calibrate if if by >+\-20%. If off, I’ll check again a couple of times to make sure it’s within range.
I have had to use multiple fingerstick calibrations with several sensors. The cgms will at times get stuck on urgent lows that are obviously wrong or error out and not be available for 3 hours at a time. Fortunately this lastest cgm is working well
I’ve been on the Dexcom G6 for several years. I may have had to calibrate the CGM one or two times, when I got sensors that didn’t work well. About the only time I regularly do finger-stick blood tests is between changing sensors (every 10 days), when I need to know what my blood glucose is while my new sensor is doing it’s 2 hr. warmup. But, I do not use the blood tests to calibrate my CGM.
I use Dexcom with the ‘no code’ method which requires a once daily calibration. It’s incredibly accurate and the peace of mind is priceless.
If it is giving a reading I question and a finger stick shows it is incorrect, then I always calibrate.
At the beginning of the session it always reads higher than it should so we calibrate then and it’s usually good to go until it expires.
When I first started using a CGM, I frequently compared it to finger stick results. That experience led me to trust my CGM more than any single finger stick. If my CGM seems “off”, I’ll do two or three finger sticks with freshly washed hands and different fingers and calibrate with the average of the results.
G6. Hardly ever 1st 10 days unless CGM seems off/wrong, either high or low. After restart a little more often.
It is a little odd. When I routinely placed DEXCOM G6 sensors on the side of my belly, I found they were erratic at night during the first couple of days (extreme lows, going off line). Since I’ve started placing sensors on my upper arm so I’m less likely to sleep on them, they seem far more reliable, so long as I manage to avoid a vein where I place them. Still, I routinely test every new sensor early on at a point where my blood sugar is level (and I use two finger sticks, averaging them, and forcing the meter to accept that average by calibrating twice with the same number). Then I do the same fairly late into the 10-day session. Usually there is no major problem, although the G6 tends to read somewhat higher than One Touch Ultra test strips. As others have said, some sensors are better than others. Overall I find the CGM a wonder that has given me more peace of mind than I could have imagined. I regret not having started using one earlier (I did start with the G4 some time ago, but a good DEXCOM had been available earlier). I still find it ridiculous that I have to renew the prescription by my doctor filling out a complex form to justify it every year — it’s not as if this problem is going to magically disappear on it own, or the benefit of a CGM somehow change. It is criminal that it took Medicare so long to cover them. While my A1c hasn’t really gone down a great deal on account of my CGM, my anxiety has been enormously reduced (especially when driving, lecturing, etc.).
Once every few sensors. I always check bs at start of sensor to make sure it’s reading correctly. I only calibrate if it is off.
I only calibrate if CGM conflicts with how I feel.
2-3 times in 10 days. Pretty nice. I’ve caught some wayward numbers that needed calibration.
I chose “Other” because there is no standard pattern to calibrations. I use a Dexcom G6 with Tandem TSlim pump. If the Sensor Glucose (SG) is plus/minus 20% of metered Blood Glucose (BG), then I calibrate. If the glucose is rising or falling rapidly, usually I wait until it has leveled off. However, if the pump and G6 are alarming that I’m low and driving me insane or I do not feel that I’m that low, I meter and calibrate to the current BG (always after I’ve treated any low).
I calibrate as recommended by my END/CDE when the numbers are very low or very high. However, I have an alert using my T-Connect App (Tandem X2 Pump/Dexcom Sensor) that reminds me every time the numbers were high or low, which using my predetermined Sensor levels.
The first thing Dex Support and Tandem Support ask is have you calibrated when you believe the sensor is failing.
Never – If an issue occurs I resolve it by replacing the sensor to change either the site or handle the software bug that the root cause.
I have a cexcom g6 that is not 100 % ,100 % of the time and carry my blood glucose meter with me at all time. It tells if my blood sugar is going up or down but I check my blood for treatment.
Dexcom not cencom.