Different readings from different monitors

if you have a read of this great article on the diabetes UK information pages it might help to explain what is happeining

Blood Glucose Meter Accuracy (diabetes.co.uk)

Glucose meters have to meet a standard which is +/- 15% accuracy

Amyp84 said:

Thanks, it’s just the difference between the two is putting me in an ‘ok’ range with one and not with the other , so it’s pointless taking readings because it’s not giving me a meaningful answer when they differ so vastly. According to one I’m ok, according to the other I’m not. How can anyone possibly base their decisions/ responses on readings that differ so much? What’s the point in testing??

feeling extremely deflated and lost with all this now. Feel I have no hope of ever getting this under control tell when I’ve got no idea where I am with my blood glucose.

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Comparing between 2 meters is not going to be a good idea for the reasons you have found out. But for testing, if you choose one meter and stick with it you can check the trends that you get from the foods you eat

so testing just before a meal, then testing 2 hours later to see how the food impacted. The 15% accuracy over time may balance out. But even if the meters were more accurate it still only measures a single point in time, so your hba1c can differ.

but also general trend is helpful, so I saw my blood levels going into double digits for a number of reads and went to doctor and confirmed my hba1c was an issue. I was able then to address that and now roughly look to see around the 5s as being my aim.

I know this is for type 2, For type 1s it’s a different aspect and I couldn’t answer as to that accuracy impact, am a bit curious myself now

Andydragon said:

Comparing between 2 meters is not going to be a good idea for the reasons you have found out. But for testing, if you choose one meter and stick with it you can check the trends that you get from the foods you eat

so testing just before a meal, then testing 2 hours later to see how the food impacted. The 15% accuracy over time may balance out. But even if the meters were more accurate it still only measures a single point in time, so your hba1c can differ.

but also general trend is helpful, so I saw my blood levels going into double digits for a number of reads and went to doctor and confirmed my hba1c was an issue. I was able then to address that and now roughly look to see around the 5s as being my aim.

I know this is for type 2, For type 1s it’s a different aspect and I couldn’t answer as to that accuracy impact, am a bit curious myself now

Click to expand...

As has been said, they all have a 15% error rate which is allowed. So it is important to try and remember this. Also, you will get different readings from different fingers, and if you're not careful and eg squeeze the finger tip rather than 'milking' from the palm of the hand (hate the term but it seems to be the accepted term!) or don't wash your hands carefully before hand and contaminate the sample.

The quality if the strip determines the accuracy too. So over the years as a T1 I have been advised to change meters to those with higher accuracy strips as and when these have come out. If you're self funding strips you might not have the luxury of paying for these more expensive ones.

It is the best tool we have for deciding insulin dosing and regime changes. You're never going to get the same accuracy as the lab processed tests, but they're not far off! Having said this, sometimes manufacturing errors happen so if you really suspect a batch of strips isn't right then you can usually contact the company for a refund. Many meters used to give calibration solutions, but many are now factory calibrated.

Testing is invaluable as long as you know the limitations. The more tests you do the better picture you get. Know patterns and trends, effects of foods, exercise, hormones (stress is a biggie for many!) and as has been said if you're using the same type of meter and strip you can compare the results to find these patterns.

Hope that helps a little?