Does overfilling a test strip cause inaccurate results?

I remember reading something to that effect. Does anyone know if it’s true, and if it is, does it result in higher or lower readings?

I'm not trying to manipulate anything, but I'm afraid someone else is.

hmmm I’m not sure with the new strips, but when dad had diabetes (and he had those bigger glucose meters of old) overfilling the strips would cause errors… or throw off results. I think it’s probably a little harder now, considering how test strips are designed.

google says underfilling causes lows, and overfilling causes highs

What did you search on to find that result?

A site that was reviewing some meters…


That’s a new one for me. With todays strips I know not enough blood will cause an error. Todays strips are designed to take in very little blood. The old strips were more fragile.

With the strips on the market today, they meter will not read the sample until there is enough blood to sample and you will get an error if there is not.

Be aware that the site lizmari noted has not been updater since 2001. If you are asking about an specific meter, you can call the company and the customer service reps or access the info on line for the specific meter manufacture to find our info.

I’m not aware of any strip that can be overloaded. Water on your finger can sometimes impact the reading. Otherwise the strips today are pretty bomb proof in sampling. Most have a material that transfers the blood to the sensor area in the strip and cannot move more than is appropriate for the sample and if not enough is used the strip will not transfer the blood to the sensor area in the strip.

Hope that helps.

Yeah, that’s pretty much what I thought, too… but back in the day, underfilling, or overfilling would’ve caused some changes… Just not so much today.

Ya, the way most strips are designed now, the strip sucks up the right amount of blood needed for the test if there is enough blood. If there is not enough, it shows the error message as S Woodward mentioned.

I also noticed that sometimes just a smidgen of the strip is still white if there is not enough blood but it will still show a result. In this case, I would do the test over because the result is almost always lower than a full strip of blood.

I’ve seen these new strips advertised on tv. I think they are One Touch. They are supposed to do a double test on the same sample of blood but I don’t see them on the net. 1/2 way down the strip it looks like it devides into 2. My Pharmacy hasn’t given me these yet though and I haven’t asked for them. I saw the new induo blue strips but it doesn’t say anything about a double test in the details of the blue ones. Maybe I was dreaming. :stuck_out_tongue:

I was having troubles with a One Touch Ultra Mini glucose meter, as being very inaccurate. When I called the warranty department, they gave me the 20% variation schpeel, but also, they sent me those double test strips… and they do, indeed, double test. :slight_smile: They’re interesting looking.

I could see this being an issue with the older photometric strips, where the sample size was critical for an accurate reading, but with today’s modern meters that rely on electric resistance to measure BG rather than a color change on a strip, I doubt it’s as big of a factor…

Huh? I have some of these “DoubleSure” One Touch strips and they look exactly the same as the older Blue ones… and I do mean exactly. The only difference I see is the added logo on the box… the vials inside are exactly the same… there’s no additional notation that some are DoubleSure and the others not.

Interesting about blood separating, position & surface tension. Explains the variation we get when re-testing. I’ve wondered what’s going when the strip doesn’t suck up blood.