I've been pretty consistent with my eating, keeping net carbs at no more than 20 and eating only in an 8 hour window. My protein level is about 60-70 gms a day. What hasn't been consistent is my FBG. Some days it is under 90 and other days it is closer to 100. I couldn't figure out why and was getting frustrated. Today it occurred to me that maybe my strips were off. I had 2 open vials and wasn't paying any attention to which vial I used. After an FBG of 98 this morning I decided to see what was happening after I ate, so 2 hours after breakfast I measured again and my bg was 104, not a very big rise. That's when I decided that the strips might just be off by 10 points. I measured again with a strip from the other vial and sure enough it read 10 points lower. I did this 2 more times today and each time one vial read 10 points higher than the other. This is frustrating. I hope the lower reading is the correct one.

Jean

From DiabetesEducator.org:

"Administration (FDA) using guidelines issued by the International Organization for Standardization (ISO) 15197:2003, “Requirements for blood- glucose monitoring systems for self-testing in managing diabetes mellitus”. The ISO standard requires that 95% of results within range or slightly elevated be within +/- 20% of the true value."

Jean, there is a thread just a few down about Accuracy of Meters, a 10 point swing can even happen with the same vial (and as quoted, 20 points is allowed). But one idea...why do you have 2 vials? is one older and has been open a while? fresh unopened strips the best and need to use them up within six months.

I know about that ridiculous standard but I don't think I have ever had 2 vials be so consistently off from each other. In general I think I have had fairly good luck with meters although having nothing to measure them against it's hard to be sure. Dr Bernstein recommends the Freestyle Freedom Lite, I believe, but it is just so expensive that I haven't bought it and go with a less expensive system. Because I am controllng my eating so well I am trying to stop worryng about my bg's but it's a hard habit to break, worry that is.

Jean

Janet,

The 2 vials were purchased at the same time. I just happened to open the second vial before the first one was empty. Neither was very old, no more than a month, and both had the same expiration date.

Jean

Some brands of meters require that you calibrate each new vial of strips using that batch's code number, so you may want to check the instructions for your meter.

The consistency between the two batches--one ten points higher than the other--suggests pretty good within-batch quality control.

Assuming that both batches are within that plus or minus 20 percent spec, the fact that those two batches don't match each other, but are otherwise consistent could actually give a narrower range of what your blood sugar might be.


90 range 72-108

100 range 80-120

overlap range 80-108.

Since you can't really know the exact blood glucose numbers, I guess the big usefulness of strips for daily testing is just showing change over time. At least you can tell that your meals aren't causing much of a rise in blood glucose. I'd just use one batch and then the other, and try not to worry about it.