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 wear 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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Never.
I do check my blood sugar with a meter once in a while, but I don’t enter the number (IE: calibrate) unless there is a large discrepancy.
Can’t calibrate a Libre2. Doing more fingersticks than I’d ever imagined. Not pleased.
Hardly ever first 10 days (G6). 2 or 3 times after restarting typically.
How do you restart? How long will the restarted sensor work?
Rob, do you find it’s less accurate after restarting? I never check with a finger stick so I can’t say, but I thought the consensus in the DOC was that the longer a sensor is in, the more accurate it is…
Never, The elimination of finger pricks after 36 years is a game changer!
With G6 I used to do it every night, but it’s so highly accurate I gave that up. Typically I do it after starting a new sensor but that’s about it.
Even with D6 must check especially the first 24 hours with a new sensor. After that only if numbers don’t seem correct. Such a relief not finger poking multiple times a day, my fingers love it! Looking forward to the D7…
The Libre 2 has been perfectly accurate since I started using this CGM three months ago. The callouses on the sides of my fingers have healed, and I don’t have to get blood from a stone. Cold hands don’t test well.
I notice that the Abbott Freestyle 14 day Libre doesn’t last 14 days for me. The readings after day 10-14 start running too low, so I just change early. Often I see blood on the insertion which is the cause.
I use Dexcom, so the session lasts 10 days. Typically, I will calibrate several times at the beginning of a session, then every couple of days. If I sense an issue–such as feeling signs of hypoglycemia when the CGM indicates a higher BG level, I will calibrate then. I will do the same for the other BG extreme. If I do a calibration at these extremes, I will check that calibration as well, usually several hours later.
The first 24 hours for g6 can be less accurate so I allow for that. Outside of that, I occasionally check but I don’t calibrate unless the numbers aren’t accurate. I do use the glucose meter control solutions to confirm the meter number but both instruments have inherent variability so I expect them to be comparable but not the same.
1-2 times in first 12 hours and a spot check towards the end. At the 8-9 day range.
Dex G6 – hardly ever. At Startup or maybe when I change Xmiters. It can be Months
I chck bl sugar by meter every nite and if not the same or close i calibrate. Otherwise I ck blood sugar if low to see if comparable
I usually need to calibrate 2-3 times at startup. After that, it is usually more accurate.
Where 2 CGM, calibrate when CGM variance exceeds 20 percent
I might be wrong but I read somewhere that collaborating actually makes your readings less accurate if you do that when you don’t need to… I don’t know my endocrinologist is proud of my A-1 C. So I just kind of move along With my dead pancreas And try to stay mindful of how I treat my body but I definitely don’t stress my health too much anymore it just becomes an obsession if I’m too focused
I’ve heard the same thing – that calibrations can do more harm than good.
I was told by my Tandem pump instructor that calibrating the dexcom makes the sensor less accurate.
not all CGM’s require calibration …… this should have been an option above.
Dexcom G6 says it does not require calibration. Still must finger stick many times per day. If the meter and the Dexcom reading are not close do two or more finger sticks and calibrate if necessary to keep in line. The meter can be wrong too. At times the Dexcom rejects the calibration and I have to wait.
The Dexcom G6 advertises as if it rarely would need calibration, but in fact I have to routinely calibrate it every few days to get it to be within even 10% of my blood glucose meter (one-touch), especially nearer the beginning of a run. I always take two meter readings then force that calibration on the Dexcom by double entering. The frustrating thing is that the G6 tends to get better over time (the first day is the worst) and about the time that I am forced to discard the sensor (since Dexcom has designed it to be impossible to extend — even if it can work perfectly — how shameful; pure greed) it seems to work most reliably. What really bothers me about the G6 is the amount of plastic waste it generates. While the G6 applicator is convenient and less “painful” (“” because the pain with the G5 was always trivial), in my experience it tends to cause bleeding far more frequently than the G5. But the G5 had an order of magnitude less plastic waste, and I was able to get two weeks from every sensor.
Sometimes I will have a Dexcom insertion that reads quite differently from my meter and I spend few days calibrating. After that it settles in and works mostly without extra calibration. Lately I have had really good sessions requiring no calibrations. I had one dex replaced this year as it kept waking me up with very wrong readings. But that was unusual. I have some scar tissue but I avoid those areas. I usually insert on stomach or back of arms.
RARELY – only if the CGM reading is suspiciously low or high.
G6, never calibrate.
I often find that the 1st day is not accurate – often 40-60 points more or less. Sometimes on the last day of the 10 days is not accurate either.
Other. I leave it (Dex G6) alone unless I get weird readings or I feel it’s really off. I usually do a finger stick within the first 24 hours to double check that it is within range (+/- 20%).
I use Medtronic so I am forced to calibrate a minimum of twice a day. Depending on timing I will sometimes do 3. I get great results from the Medtronic sensors although I know not everyone does. Reading these comments it’s obvious not everyone gets great results from Dexcom either. My sister uses Dexcom and wound up in DKA a couple of years ago. Just because you DON’T have to test with a meter doesn’t mean you shouldn’t!! They are not perfect and I’m amazed the FDA allows no testing.
I use the Dexcom G6 and while it doesn’t require calibration, I choose to use the ‘no code’ option which requires a daily calibration. I takes just a minute and my Dexcom is almost always accurate within 10 points. The peace of mind that comes with this option allows me to trust the device the other 23 hours and 59 minutes.
I usually calibrate my Dexcom G6 2-3 times per session. It seems to make it slightly more accurate, although probably not necessary.
DEX – G6. No routine calibrations. Often after the start-up of a new sensor, I will see a reading that seems strange for the trend and time of day. Those often need a meter check and calibration. Sometimes it takes 2 or 3 calibration adjustments to get smooth out with reliable readings.
People always seem to assume that when the Dexcom 6 and the meter disagree, the meter must be correct and the Dexcom incorrect. However, both have been proven to be equally accurate. So after I started using the Dexcom 6, I just assumed it was always correct. I would only test during the 2-hour warmup period if it was time for a meal and I needed my pre-meal blood sugar.
However, about 2 weeks ago, I had a very strange reading after inserting the Dexcom, so I tested and the Dexcom seemed completely wrong. I used two meter sugars to calibrate it (which were pretty close to identical). About 4 hours later, it seemed wrong, but not so far off. So I did two sugars with my meter, which were identical, and calibrated again. After that, no problems – it was back to normal behavior. So except for two weeks ago, I basically had not done meter sugars for about 18 months.
When I was on the libre, I couldn’t calibrate and my A1c average came back 20mg higher than what the libre predicted. I was really frustrated. I got a dexcom g6 and I am now calibrating once a day average. The first day is usually 3 times. Then I generally trust it.
I only calibrate when my symptoms do not match the CGM results.
Never or Rarely, maybe 2 or 3 times a year (if that much) when/if DexG6 readings seem a little bit off. I occasionally self-test with a Contour NEXT meter while a new G6 sensor is in warm-up period but I don’t calibrate. I trust how Dexcom functions and have had consistently reliable experience with it.
I use an old One Touch meter, MDI, & and Dexcom G6. From chapter 4 of Dexcom G6 manual: “But sometimes you must use your meter instead of the G6…”when in doubt, get your meter out.” “You don’t have to calibrate, but you can.” Since my pharmacy refuses to sell me syringes marked in half units, I must eyeball for 1/2 unit delivery of insulins. People with pumps have the advantage of being able to really fine-tune the amounts & times of delivery. Would that be a factor in explaining why some folks can go months without calibrating? I sometimes must calibrate every couple of days. Calibrating over several months helped me avoid needless alarms yet still keep in the 70-130 range 95% of the time.
InPen allows .5 unit doses and also gives you the tracking, does the math, etc that a pump does. I adore mine. You just use cartridges that fit inside the reusable pen, same needles as other pens, and the InPen battery lasts a year.
Never. Have never encountered a situation where there was a system issue requiring calibration.
When I have an unusual series of readings or when a very low reading occurs and I don’t “feel” it.
I regularly check finger sticks, so I calibrate if the CGM is consistently off by more than 10-20 mg/dL. Sometimes multiple times for a sensor, others not at all
Libre 14 day user. Not “calibrating”, more like correlating. The Libre is consistently reading 30-40% low compared with 2 different BGMs, so I don’t really trust it that much. At least it is off by about the same amount, no matter whether the sensor is new or 8 days in use. CGM is about 4 months old. I do the math in my head. I know if the reading is 60, BG is actually about 90; if the reading is 120, it’s actually about 180
I only calibrate if BG differs from SG by +- 20%. When I am stressed, the Dexcom sensor sometimes will show a skyrocketing SG while the BG is still in range.
At first I checked at least once when inserting a new sensor, as I didn’t trust Dex G6 yet. Now only check with blood if something seems really off compared to my carb intake or ?? Occasionally after inserting a new one, it bounces up and down for several hours. That’s probably only once every 4 sensors.
Yes only because my supplies rum out because the has to get approval from the insurance company. Except this scenario I never use re calibration with a glucose meter
When the cgm is some what off from my finger prick / glucose monitor.