Type 2 I Have Serious Doubts On The Accuracy Of Freestyle Libre.

I’m using my first sensor and have only 3 full days (and 4 nights) of data, so not conclusive at all. However, I share your concerns.

In my case the Libre has been consistently higher and with pre and post meal readings showing the most variance - not just higher but a bigger jump. Then all of a sudden this morning, my FBG was lower (by a full 1mmol) on the Libre.

Jury’s out but the cost doesn’t encourage much experimentation, especially since my code free has shown a monthly average which has remained constant (within 0.1mmol) since October, on a regime of at least 7 tests a day.

I’ve had my first accurate one and it’s the 5th one I’ve put on. Keep spending that money!

From what I've read on this forum, and from my own experience, the official Libre reader seems sometimes wildly inaccurate. I now use Glimp exclusively, as it can be calibrated. I would say nine out of ten readings are correct with it. It doesn't account for a bad sensor, though, which can happen.

I don't tend to rely on the Libre for accuracy, what's more important for me is to see direction of bg because if I can see a down ward trend it helps me to avoid going hypo or hyper to take more insulin and for patterns so I can see overnight fasting rates. As its testing from fluid in the subcutaneous tissue it will rarely report the same reading as a bg meter as its delayed by around 20 minutes. I rule out the first 24 hours also while it settles in and sometimes find where it is sited can also affect accuracy too.

This sensor has been spot on for 2 weeks. And I didn’t leave it in for 24hrs. I did 60 mins as per instructions. So, just goes to show.

In the 3 odd months since I've been 'lucky' enough to have obtained one on prescription I've had no problems at all, quite it's a life changing device and the accuracy is surprisingly good.

I'm only blood testing to drive these days, or for the odd calibration check but I find it near enough to bolus from, the Libre (or cgm) is quite a big help for T1 management.

I've even found their customer services to be helpful.

Goonergal said:

I’m using my first sensor and have only 3 full days (and 4 nights) of data, so not conclusive at all. However, I share your concerns.

In my case the Libre has been consistently higher and with pre and post meal readings showing the most variance - not just higher but a bigger jump. Then all of a sudden this morning, my FBG was lower (by a full 1mmol) on the Libre.

Jury’s out but the cost doesn’t encourage much experimentation, especially since my code free has shown a monthly average which has remained constant (within 0.1mmol) since October, on a regime of at least 7 tests a day.

Click to expand...

I was made aware of the diff in libre vs blood measuring when I got mine. I find the arrows and their direction of much more use than the actual readings. I have no hypo awareness and the arrow direction invaluable to me to show me steep : quick declines in BS’s.

My experience is that the sensors take a few days to settle down, the first day is a bit inaccurate, particularly with low readings, but then over a few days it becomes more and more accurate. My current one is into it's 11th day, and I trust it completely now.

I did have one that was never quite accurate, but the value of them, for people using insulin, is enormous, it's life changing.

But if you aren't in that situation then finger pricking might be a lower cost alternative that works better for you.

Im on Gliclizide with some hypos.
Ive been using FS Libre most of this year. Initially I had few problems - 1 out of first 9 or 10 sensors was so inaccurate ( consistently showing either half or double the BG obtained via fingerpricks that it had to be replaced by Abbot while the others were acceptably accurate ( not spot on but predictably different) and still useful interms of trends.
The last 5 however have had multiple problems ranging from wild inaccuracy, to complette failure, to poor adhesion and only 2 of them has been problem free.( and 1 of those came off with a slight knock while getting into my car)
For me a drop in quality to only a max of 40% of sensors functioning is something thats decided me not to shell out for any more sensors and to wait until either the price drops v significantly ( unlikely) or quality / reliability demonstrably improve ( likely be it libre or one of the increasing number of competitors)

Another thread on same topic https://www.diabetes.co.uk/forum/th...-highly-inaccurate.137681/page-5#post-1813680

Unfortunately, according to my FreeStyle Libre meter reading, I've been experiencing severe lower readings that at times I was under the impression that I was experiencing severe hypoglycemia. The fright and experiencing heightened to the point that I was afraid to drive or event exercise for almost four days until I contact my doctor's office and was advised to prick my finger and measured my blood sugar level. Sadly, I discovered that the variance between pricking my finger and scanning my sensor using the Freestyle Libre was an average of 3.2 higher when pricking my finger. What's more frightening was the fact that there appears to be a rapid decline in my blood sugar level within 1 1/2 hour after eating (meal), thus resulting in me seeking to find appropriate food supplements to spike my sugar level.

Much to my delight, since complementing using the Freestyle Libre scanning along with pricking my finger not only am I experiencing the huge variances (much higher reading when pricking my finger) but take comfort in the fact that I'm not endangering myself. It's been pointed out that the inaccurate reading when using the Freestyle Libre meter could be as a result of incorrectly placing the sensor on my arm. My Doctor advise that when the sensor requires replacing that I should have it placed at the sofer tissue area of my arm. Please advise.