I’ve been using Accu-check Aviva test strips, with great accuracy (Blood Glucose to A1C, for 7 years. I am currently using Tresiba and Metformin, diet and exercise for blood sugar control. My blood sugars tend to be very stable. Every once in a while, I check into the Tu Diabetes Forum, and have been looking forward to trying the Freestyle Libre. Well, I got one day before yesterday, inserted the sensor and have been using it for the second day now. The ISF readings from the device are consistently an average of 30 points higher than my blood glucose meter. Every time! My lines are flat; no highs or lows. It does not seem like it’s a lag time issue, but a calibration issue. I phoned Abbot’s help line, which was not helpful. After asking me 25 minutes of questions to determine if there was user error, and not finding any, they said I needed to talk to my physician. Really? The only thing I have not yet done, is, use the Freestyle Libre Precision Neo test strips that go with the monitor. I ordered some today, to arrive on Monday. I’m anxious to see if the whole unit is not correctly calibrated or if the ISF reading is wholly different than blood glucose test. If anyone has any thoughts or feedback, I would be most grateful. Have never had experience with a continuous monitoring device,
Hmm…I’ve been hearing people are having issues like this. My CDE said to be sure to have a meter available because this really isn’t going to fly as a no fingerstick way to test. I was going to get it for trending information only as I also do not have a CGM. Please keep us informed if you figure it out and best wishes with it.
Will do, thanks.
Unbelievable that they refer you to your physician. I’ve never had that happen when discussing sensor issues with Medtronic. I have had overly lengthy phone calls because of the problems with the enlites but I’ve also had them send me more than 22 replacement sensors in the course of a year. So ultimately they take responsibility.
I have been using my Freestyle Libre for about 4 days now and notice that is it constantly about 10-20 points higher than the freestyle meter built into my Omnipod. Rarely have I heard of a CGM being consistently spot on with a “finger prick meter” as they use completely different methods to monitor your BG. My friend’s Dexcom is always 10-20 points lower than her finger pricks. 30 points does seem like a bit much to me though… I have yet to try the precision neo test strips with the proper control solution either and would be curious to hear what you come back with after running your test. I thought about buying some but I have a large stockpile of Freestyle test strips already and can’t really justify paying out of pocket for more of the precision neo just for that. Keep us updated! I’m sure there will be some quirks to work out for all of us but I guess that is the cost of progress. Just in these few days I feel like I have learned so much about how my body reacts to food and It is great to see what happens to my BG as I sleep 
"Rarely have I heard of a CGM being consistently spot on with a “finger prick meter”
I hate to burst your bubble Benjamin but I have a Dexcom that is often either exactly the same as my meter or just a few points off. Same thing occurs with my wife’s Dexcom. So unless you try one you won’t know how accurate it is personally. there are many posters online who are very happy with the Dexcom accuracy. I used to be skeptical when I only had used the Enlite, but now that I have one myself, it’s impossible to be skeptical because accuracy is the norm; not the exception.
I wish I had the same good things to say about the Enlite system which for me was pretty much worthless. I had so much trouble with it that Medtronic replaced at least 22 of my sensors with in roughly a year
lol you didn’t “burst my bubble” Dave. Believe me! 
I use the Dexcom 5 and almost all of my numbers are off compared to my meter. Very rarely are they right on.
It’s possible you might have a bad sensor. I’m on day 6 of the Libre and it’s correlated very closely with my Contour Next meter. I’ve found if the Libre gives me a flat arrow with my reading and I do a fingerstick immediately, it’s always within 2 points. If the Libre shows my sugar trending up or down, then it’s about 10 minutes behind what a fingerstick will give me, but again, always within 2 points. I’ve been quite pleasantly surprised with how accurate it is.
How long have you been wearing the Dexcom, Bev? Where do you wear it? Do you have periods of stable bg’s so that you can successfully calibrate it? Do you take a med with acetaminophen? Are you well hydrated? Have you spoken with tech support?
I’ve had just one “bad” sensor" since Sept 12. In a couple of days, that makes 3 months of using the Dexcom. My wife and I both find it incredibly accurate. Like crazy accurate. Sometimes after not having been calibrated for well past 12 hours, the Dexcom is exactly the same as a meter reading, and otherwise off a few points. When it it off by more, most of the time if I check it in 15 minutes, it will then correlate well with the meter reading of 15 minutes prior.
I have been on the G5 about 6 months. At the beginning I called tech support and was told it was getting used to my body. I was diagnosed in May 2016, I always have the sensor on my abdomen. I do not take anything with acetaminophen. I do drink water on a regular basis to stay hydrated. My numbers most always fall within the 20% so I just go with it. It is just a very rare case that the numbers are right on.
I started to an A1C of 10.3 and it is not 7.2, so it is getting there and I am still on MDI, Lantus ad novolog.
Congrats on getting your A1C down to a much safer level. That’s so important as you know. It sounds like you’re doing everything necessary to have the Dexcom work well so it must be frustrating for you. I had that same experience when I used MiniMed Enlite sensors. Nothing I could do would make them work for me
Freestyle Precision Neo test strips will arrive today. I’m anxious to see if the test strip numbers on the Libre device correlate to the scan/sensor results or the Accu check test strip results. I quit taking vitamin C to see if that made a difference in the numbers, but it didn’t. It seems like the lower my blood glucose, the closer the IF and test strip results.
90 minutes after breakfast: Accu check test strip reads 55 and Libre scan 92! Go figure!
Try scanning the Libra 15 to 20 minutes after the reading you mentioned and see if that correlates better with your strips
I tried Libre before it became available in the US (bought it from Ebay) and what I didn’t like about it was inconsistency between sensors. Some were spot on from very start to the end, others were way out and never corrected themselves. May be it weren’t the sensors, but the place there were inserted in or a similar issue. The bottom line - I was never certain if the sensor I was about to insert would show correct numbers or not (I was using Freestyle Lite meter for measurements).
2.5 hours after breakfast: Accucheck 62, Libre 87. Having never used a monitor, this is all new and interesting. Hadn’t really considered deviations between sensors; I’m still on the first one. Was trying to get away from so many finger sticks everyday, but this isn’t very promising so far.
I just had a similar experience with Abbot. I told them that was not an acceptable answer to my issues of having differences with my readings of 30-50 points per reading even with an adequate compensation for normal CGM/BG lag times. They gave me a code to give to my pharmacy for a brand new Libre meter. After some more coaxing I got one for a free sensor too. I figured that it is only fair as this sensor is basically a waste now. You might try calling them back and seeing what they can do for you. I admit as well that this is not a promising start to the Libre system.
This is why my CDE suggested using the Libre for mostly trending info and not much else…
Freestyle Precision Neo test strips are almost spot on with the Accu-Check meter readings. However, the sensor readings are still consistently 25-40 points higher. (No trending up or down, just flat arrows) No matter if I scan at the same time or ten minutes later, the discrepancy is there. It is not a lag time issue. So, I did phone Abbot back, and after another long and frustrating call, they agreed to send the coupon codes to replace the sensor. It will surely be interesting to see if the sensors are as unpredictable as some have experienced. Thanks to you all for your feedback.