Jonah - thanks for the info that Aviva has more filters in its strips that is good to know - in fact this a.m. I just checked my fasting (before Metformin ER) and it was 113 for the Aviva and 117 for the Micro relion… YOur info is very valuable and I will store it soemwhere in my brain for later use. Thanks again for your participation in this discussion.
Anthony - wonder if they make any 60 second meters now? It would be great if we can that kindof accuracy. I am happy to sacrifice seconds for accuracy.
The whole test strip accuracy thing is a travesty in my opinion. And I am mincing my words. The meters have only been required to be accurate to +/- 20%, a terrible level of accuracy, especially if you are dosing insulin based on those readings. The FDA is looking at tightening things up, but I would be absolutely shocked if we saw a home meter with +/- 5% accuracy.
That being said, Dr. B currently recommends the Aviva based on his testing. In my experience, even repeatability in current strips is generally not within 10%, as further evidenced by your tests.
In the end, I decided that chasing the best meter was not going to gain me much. What would gain me a lot was properly controlling the variables that I found that distorted my readings. I wash my Finger Under Test (FUT), I’ll not squeeze the FUT to avoid getting a bunch of plasma (some people use the second drop), never let the test strips get too cold or too hot, and never ever leave them exposed to humd air, etc.
I always bring my meter for fasting blood sugar draws and compare my meter reading with the Lab. My OneTouch has had a good correspondance (+/- 10%).
ps. Precision is actually a measure of the smallest difference which is reported, commonly denoted in science and engineering by the significant digits reported, which for basically all these meters is precision of +/ 0.5 mg/dl. If the meter read 98.1 mg/dl, then the precision would be implied to be 0.05 mg/dl.
pps. Accuracy on the other hand is a measure of the variability around the true value. Since we don’t know the true value here, we can be fooled into thinking these meters are good when they are actually all cr*p and your blood sugar is really 200 mg/dl.
ppps. Did I mention that home meter accuracy is a travesty and I think they are cr*p?
A while ago, I too did the test on a few different meters that I have. Accu-chek Avia, Compact, First step?? something or other & yet another I cant remember… I did get different #s. I first thought, well 2 of them have that vial of stuff to check the accuracy for every new test strip vial you use…maybe strip problem? Then upon reading them I did see that the Avia & Compact were made by same company and supposedly more accurate with its technology.
I happen to be at my nutritionalist and thought I would throw my theory & my testing and research at her,
She explained it as the following:
If you were barefoot and dipped your toe in a stream, then dipped it again, you would never touch the same water, it would be always different-the same goes with your blood droplets.
I thought “A very strange example, but she is exceptionally bright, and on the ride home…it did make sense.” I actually did an experiment with only one of my meters kept testing same puncture 5,6 & 7 times…all different results!
Hey smallboo - thanks for the reply - yes - I have heard that about testing the blood sugar before - but never as clearly presented as you just did. It really makes a very clear picture. Thanks for participating. Nice hot yellow car!!!
I fully agree I would gladly wait longer and would measure more often. Now my BG is such that what I get out of a measurement is mostly random noise.
Contour I have also reads high I suspect. To counter this I do not measure as often and inject the insulin on a time basis instead of based on measurements.
Precision is usually reported as one standard deviation not to be confused with the smallest reading on the scale. I agree that the squeezing of fingers and other stuff can have some effect. But the biggest problem is the 5 second measuring time witch only allows time for an amperometric method and not the coulometric method used with the 60 second meters.
If the meter measured exactly the same drop of blood over and over it would still give you very different readings. The amount of reacting chemical in the strips varies from strip to strip and the measurement of how much chemical has reacted is also very inaccurate. So she was just muddying up the water instead of standing up for diabetics needs for accuracy, the more so when you are on insulin. It is people like her and my Endo that do great disservice to diabetics.