Meter Conflict

Hi guys. Okay, so I purchased a new Freestyle Insulinx glucometer because it accepts smaller blood drops. I got a pretty good sized drop today, so I did a test with both my original Accu-Chek Aviva Connect and my new Freestyle Insulinx.

From the same sample, I got 14.4 mmol/L on my Aviva, but I got 12.2 mmol/L on my Insulinx. Are the readings typically that different? I’m not sure which value is closer to the actual value, aka which one I should trust - some advice would be much appreciated!

Edit: I’m hoping to pick one tonight so that I know in case I don’t get a big enough drop tomorrow to use both (likely).

 

All meters have a 20% variance. The "actual" number is probably in the rehlm of 13ish.

 

Are you sure? The reason I worry is that I pretty consistently get an evening pre-shot blood glucose on Lola of 14-15 mmol/L. Is there literature on meter variance?

 

You'll have to Google regulations on glucose meter allowed variances. I think it's 20% in the USA. Looking at it that way, those two readings are within 20% of each other. One of the many crazy-making parts of BG measurement.

As we always say to people, pick one meter that you like and stick with it. Comparing the readings from two meters is guaranteed to drive you nuts. Basically the trends are important - too high, good range, too low. You can learn what numbers those translate to on the meter of your choice.

 

This document probably includes more than you ever wanted to know about blood glucose meters and reasons for errors or discrepincies, but is known to be a reliable source of information: Factors Affecting Blood Glucose Monitoring: Sources of Errors in Measurement (Note: BG numbers are reported in the Imperial system used in the US)

"A few years ago, the International Standards Organization (ISO), in conjunction with international regulatory authorities, health care providers, and device manufacturers in many countries, established a standard for evaluating the accuracy of blood glucose meters. Called ISO 15197, the standard calls for a minimum accuracy. Ninety five percent of all measured values should fall within

• 20% of glucose values above 75 mg/dl
• 15 mg of glucose values below 75 mg/dl.3"

The FDA (US) has now recommended meter manufacturer's tighten up their accuracy standards to +/-15% for home-use meters and a tighter +/-10% for clinical meters.

BTW, since the FDMB is based in the USA, you'll usually get more replies to questions if you convert metric numbers to the Imperial system. Simply multiply the metric number by 18 or use this Blood Glucose Converter Calculator: http://www.felinediabetes.com/bg-convert.htm

 

Also see:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2769957/

 

FWIW, I'm a diabetic and Accu-chek tend to be more accurate meters than any other brand. However, the strips cost more. All meters manufacturered after Jan 1, 2017 must meet the new 15% guidelines of accuracy. Accu-Check met that before the guidelines were initiated. So, if the manufacturing date on your meter is 2017 or later, then just pick a meter and stick with it. FWIW, I use Bayer Contour Next.