“Choose Your Blood Glucose Meter Wisely!” by Gary Scheiner
“Our team believes that meters should be within 10% of lab values (or within 10 mg/dl of lab values when in a low range) to be considered sufficiently accurate.”
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I have some things I’d like to add, things like accuracy versus precision. And why precision can actually be more important!
When I get some minutes. 
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It’s “repeatability” not precision that matters… 
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I think you are agreeing with my point but maybe confusing accuracy and precision.
Repeatability and precision are basically the same.
I said:
References:
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The precision of a measurement system, related to reproducibility and repeatability, is the degree to which repeated measurements under unchanged conditions show the same results.
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JCGM 200:2008 International vocabulary of metrology — Basic and general concepts and associated terms (VIM)
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Taylor, John Robert (1999). An Introduction to Error Analysis: The Study of Uncertainties in Physical Measurements. University Science Books. pp. 128–129. ISBN 0-935702-75-X.
I think precision (what you are referring to as repeatability) can help you with finding changes in BG better than accuracy.
If you are always 20 above the real value (worse accuracy, better precision), you can still find your slope and rate of change. And if you know the 20 point difference, you can adjust and be fine.
But if you are sometimes 10 above and sometimes 10 below (better accuracy, worse precision) you have a harder time with rate of change and slope. You know you are within 10, but the changes are harder to know.
This is particularly helpful when you do tests a few minutes apart.
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Just an old joke Eric, don’t worry. Yes I completely agree that repeatability is far more important than average accuracy…
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Cool. You gotta help me with those things, I was a newbie on the old site, so I don’t know all the inside jokes. But it is cool we are on the same page about that. Many people think the other way.
I talked to the Agamatrix meter people today. I will give it a try, even though it did not fare too well on Schiener’s list.
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Ugh. This is less than encouraging. Was looking at buying an Agamatrix meter as a cheap second meter. Cheap strips. But after seeing the Gary Schiener review, I took a look at some random user comments. I saw a few reviews like this on Amazon.
(NOTE: Below is not my review, just some Amazon person’s. But this kind of stuff makes me think more than twice about spending money on a meter like this. Anyone here use this one?
SOME RANDOM AMAZON REVIEW:
I had been using the Accu-chek Avivia Plus meter before buying the Presto meter. Was hoping to be able to save a lot of money as the Presto’s test strips cost less than half the Accu-chek. The first day I got the new Presto, I ran parallel tests with the Aviva over the course of 15 minutes, with both machines being used seconds apart from each other from the same lancing. Here are the results of the first test series:
Aviva Plus: 134 - 125 - 130 - 135
Presto: 147 - 153 - 137 - 155
Two hours after a meal I did another test with two readings of each meter taken two minutes apart:
Aviva - 119 - 122
Presto - 162 - 137
The final straw was after dinner. The Accu-chek read 121. I did 3 consecutive readings with the Presto using a fresh lance site (same finger) each time - the first was 176, then 102, then 117!
The numbers speak for themselves - the Presto was all over the place with variances of over 70 mg/dL just minutes apart. The accu-chek varied slightly, but most were within the published specs. In addition the Presto was usually way higher than the accu-check, and way higher than what my doctor had been reading.
Maybe I got a lemon, maybe it’s my technique, but I tried to follow the instructions precisely (and there are lots more warnings about what to avoid to get an accurate reading than with the accu-chek), including using the test solution to verify the meter before testing, and wiping away the first drop of blood, then squeezing another drop out before taking the reading with the Presto (something you don’t have to do with the accu-chek). The run with the test solution was only 4 points below the maximum acceptable reading, which to me indicates that this unit was usually giving false high readings.
Conclusion - this was a waste of money. I will take it to my doctor to compare with their readings, and if anything changes will update my review, but I have to conclude that the Presto I received is not only inaccurate (high), it is highly inconsistent in it’s readings and can not be trusted.
That matches my experiences with a number of different meters… but we all have unique blood chemistry and the bottom line is that we have to find the meter that works reasonably well for us… so although other user reviews do have some value, really it only matters how well it works for the end user, not for someone else…
Been burnt so many times on crap meters. The last 3 or 4 cheapies that I bought have sucked. I’m gonna keep shopping around.
What is your main meter Sam? Not your second tier, but your top shelf go-to meter?
Mine is the FreeStyle Lite. Problem is, those strips are expensive.
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Currently my top shelf is the one touch verio flex… not by choice but because that’s the only strips my insurance covers, but that’s a whole different rant… There is no such thing as the perfect meter. Throughout the vast majority of my D history I bought truetest strips with cash and was pretty happy with them as my primary, but unfortunately they’ve been discontinued (interestingly, their prices have skyrocketed on eBay since they discontinued them… seems they have a cult following)
Have you tried the Contour NEXT USB? I have a much higher copay for the strips but feel it’s worth it.
I am not a fan of the NextOne. Ascensia sent me one gratis. One look at the permissions required by the app (iphone and android) sent me running!
I ordered one, it’s on the way. That is my next one to try. The cost of strips was not too bad.
If you ordered a Contour NEXT USB, please share your source. Ascensia claims they have none of the discontinued meter left in stock.
I ordered it on Amazon!
I didn’t know it was discontinued.
No worries, Eric. The USB version has been a great meter for me. It uses the same strips as the newer meter. You just won’t be sending Ascensia gigs of data.
Let me know which seller and meter version you receive…
I will let you know. And I don’t send data to anybody! I just do my own thing.
I am curious to hear what the get from you, why you said this:
Well, they won’t get anything from me as I’m not willing to trade my security and privacy for a few bells 'n whistles. Go look at the permissions details in the Play Store.
Edited to add >> https://play.google.com/store/apps/details?id=com.ascensia.contour.us
