Are Pet monitors really "off" by 40 either way?

[Onre]

One veterinarian's office told me this when I discussed home testing. They said the the number can be off by 40 higher or 40 lower when I grew concerned that my cat's glucose was at 57. She is often in the 360-380 range so I am curious.

 

[Shoeskitty-GA]

All glucometers, both human and pet, are legally allowed up to a 20% variance from the lab equipment at your vet's office. This means that the number you see on your glucometer can be more or less than as much as 20% than the lab equipment at your vet's office. So theoretically, that 57 on your meter could have been as low as 46 or as high as 68 on the lab equipment. The difference will be greater when your glucometer is measuring in high numbers.

edited to add that a human meter will register lower than the pet meter always because the blood glucose is measured in a human is different in a pet.

 

[Tuxedo Mom]

The higher the reading the greater the difference between a human meter and a pet meter. You cannot use "40" as a set number difference. For instance I did a reading on the AT2 meter of 86 and got a reading on the Free Style Lite of 65. Another time I did a reading on the AT2 of 43 and got a reading of 31 on the Free Syle Lite meter. Another time I did a reading of 499 on the AT2 meter and got a reading of 311 on the Free Style Lite meter. These readings were all done with the same blood drop each time. The higher the reading the bigger the difference between a pet and human meter.


Pet meters will always read higher than a human meter because a kittiy's blood distribution is different than a human's. However as long as you use the same meter and follow the guidelines it will tell you what is happening with a certain dose.

 

[JanetNJ]

Alphatrak meters have a 15% variance. Human meters have a 20% variance.


57 on an Alphatrak is too low so you are correct to be concerned . You want to keep it above 68... 68-150 is normal. If it goes under steer up with food or honey as needed.

 

[Larry and Kitties]

Page 2 of the following give the ISO specs for meter accuracy. Note that at lower BGs (less than 75 the accuracy is +/- 15 points). For greater values the accuracy is +/- 20%
http://www.diabeticlivingonline.com...d-sugar-blood-glucose-meter-accuracy?page=0,1

Human meters have a 20% variance.

Just wondering where you found the accuracy of the AlphaTrak as +/- 15%

Alphatrak meters have a 15% variance.

 

[Shoeskitty-GA]

I wondered about where that 15% came from as well. Zoetis will tell you that it's 20% also. I had to call them last year because I had a 35% discrepancy from the meter with the Vet's Lab Equipment and was reminded that they were allowed to vary by as much as 20%. Hoping that the 15% is accurate since I use the AT2, but don't believe it is.

 

[JanetNJ]

Page 2 of the following give the ISO specs for meter accuracy. Note that at lower BGs (less than 75 the accuracy is +/- 15 points). For greater values the accuracy is +/- 20%
http://www.diabeticlivingonline.com/monitoring/blood-sugar/checking-blood-sugar-blood-glucose-meter-accuracy?page=0,1



Just wondering where you found the accuracy of the AlphaTrak as +/- 15%

It was in the reading material that came with my meter.

 

[Shoeskitty-GA]

It was in the reading material that came with my meter.

Thanks. I will reread my paperwork with both of mine.

 

[JanetNJ]

Thanks. I will reread my paperwork with both of mine.

Or maybe it's it somewhere else. I'll look when I get home. I know they say the average variation for cat readings is 5.3%.

 

[JanetNJ]

I wondered about where that 15% came from as well. Zoetis will tell you that it's 20% also. I had to call them last year because I had a 35% discrepancy from the meter with the Vet's Lab Equipment and was reminded that they were allowed to vary by as much as 20%. Hoping that the 15% is accurate since I use the AT2, but don't believe it is.

Eh maybe I am wrong. Maybe I saw 15% on amazon or something and I just have it in my head wrong.

 

[manxcat419]

Completely agree that there is no "fixed value" for the amount a meter will be off by on any given reading. The +/-20% variance does exist, but if you use the same meter every time (whether that's a pet meter or a human meter), you would expect the majority of your tests to fall well inside that maximum variance. Variance between 2 different meters is likely to be greater - if you have a meter than is more likely to read close to the +20% and another one that is more likely to read closer to the -20% all other things being equal, then you could see a huge variance in numbers if you try to "verify" the results from one meter on a different one.

Interesting to note is that the accuracy results for the Alphatrak 2 are listed as an average only and were obtained using venous blood samples - which is not what we use when we're testing at home. FDA guidelines for human glucometers state that the accuracy should be tested using capillary whole blood...in other words that the accuracy testing should be done using the same type of sample as people will obtain at home. I have searched, but am currently unable to find any FDA document stating a required variance maximum for pet-only meters...and have seen a number of reviews of the Alphatrak where people claim to be able to get readings from over 400 all the way down to the mid-100s with the same drop of blood. While I would hope that that is user error only, it does raise a question over whether or not the pet meters are really produced to the same standard consistently as the human meters. Also to note - if your vet is regularly seeing a variance of 40 full points between an Alphatrak at low numbers and the lab, I consistently see much less variation from lab in the normal range or close to it with the basic ReliOn meters with a general variance of around 4-5 points only with a cat running in normal range.