Which blood glucose checking machine is more accurate

biren1973

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119
Type of diabetes
Type 2
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Hi,

I have been using GlucoNavi Blood sugar meter for past few years. Usually my morning blood sugar is always less than 6, but for past few days I can see the meter was giving more than 6.5 even without any high meals previous night.

So I recently bought another BG meter GlucoRx Nexus Blue. I did the measurements on both after dinner which came as 7.2 for Glucorx and 6.7 for GlucoNavi.

My question is can the two different meters give different reasults?

Anyone know if there is any blood sugar meter that is more accurate to what GP tests?

Also is there any procedure how to measure it? For example I wash my hands by soap and dry it with kitchen tissue before testing, do you think it's right approach to do?

Appreciate anyone replying to my message.

Regards
 
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catinahat

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My question is can the two different meters give different reasults
Yes two meters will almost certainly give different results, in fact if you immediately repeat a test using the same meter and the same drop of blood its entirely possible to get two different results.
Anyone know if there is any blood sugar meter that is more accurate to what GP tests?
All of the meters have to be manufactured to the same accuracy standard of plus/minus 15%, including the one your Dr uses
I did the measurements on both after dinner which came as 7.2 for Glucorx and 6.7 for GlucoNavi.
Both of these results are well within the 15% margin of error, there is only a 0.5 mmol/l difference between the two. The meters really are not all that accurate, they just give us an idea of where our blood sugar is
The 6.7 result for example just tells you that your actual sugar level is anywhere between 6.0 to 7.5
Usually my morning blood sugar is always less than 6, but for past few days I can see the meter was giving more than 6.5 even without any high meals previous night.
This doesn’t particularly mean that your meter is faulty, it just shows that for the last few days your levels have been slightly higher. Anything can affect our blood sugar levels, maybe you had a restless night or perhaps you have a cold brewing or are a little stressed over something. Food has the most impact on our blood sugar but almost everything we do or even think can cause our levels to change.

Also is there any procedure how to measure it? For example I wash my hands by soap and dry it with kitchen tissue before testing, do you think it's right approach to do?
Absolutely perfect, washing makes sure there is nothing on your fingers to give a false high,
And drying ensures there is no moisture to dilute the blood sample and cause a false low.
 

jjraak

Expert
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Type of diabetes
Type 2
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Yes two meters will almost certainly give different results, in fact if you immediately repeat a test using the same meter and the same drop of blood its entirely possible to get two different results.

All of the meters have to be manufactured to the same accuracy standard of plus/minus 15%, including the one your Dr uses

Both of these results are well within the 15% margin of error, there is only a 0.5 mmol/l difference between the two. The meters really are not all that accurate, they just give us an idea of where our blood sugar is
The 6.7 result for example just tells you that your actual sugar level is anywhere between 6.0 to 7.5

This doesn’t particularly mean that your meter is faulty, it just shows that for the last few days your levels have been slightly higher. Anything can affect our blood sugar levels, maybe you had a restless night or perhaps you have a cold brewing or are a little stressed over something. Food has the most impact on our blood sugar but almost everything we do or even think can cause our levels to change.


Absolutely perfect, washing makes sure there is nothing on your fingers to give a false high,
And drying ensures there is no moisture to dilute the blood sample and cause a false low.
Very nicely explained... :cool:
 

jjraak

Expert
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Type of diabetes
Type 2
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Hi,

I have been using GlucoNavi Blood sugar meter for past few years. Usually my morning blood sugar is always less than 6, but for past few days I can see the meter was giving more than 6.5 even without any high meals previous night.

So I recently bought another BG meter GlucoRx Nexus Blue. I did the measurements on both after dinner which came as 7.2 for Glucorx and 6.7 for GlucoNavi.

My question is can the two different meters give different reasults?

Anyone know if there is any blood sugar meter that is more accurate to what GP tests?

Also is there any procedure how to measure it? For example I wash my hands by soap and dry it with kitchen tissue before testing, do you think it's right approach to do?

Appreciate anyone replying to my message.

Regards
As per @catinahat & other replies.
The meters aren't entirely accurate...none of them are .

I read up when first on scene, & while I understand the need for pinpoint accuracy, I doubt any ever could offer that .

And given that many things can raise our BG, infections/illness being just one, it's a constant game of reading between the lines & deciding what is causing any recent rises (or lowerings )

The best I think we can hope for is a trend of numbers up or down to guide & help keep us safe.

I likened not knowing our testing numbers to being in a long corridor, In the dark trying not to hit the walls or trip over as we fumble our way along it.

The meter just shines a light so we know when we are close to the walls, and in danger of bumps & bruises ...aka making us stop & consider what might be causing it and what to avoid/ prepare for

If we follow the light (numbers) we can likely avoid too many hits over the forthcoming years .

Well, that's how I see it.

Others may have a different view .
 
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plantae

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830
Type of diabetes
Type 1
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Insulin
I've got two meters (in addition to my Libre). Since it was time for my post-prandial test anyway I decided to do an experiment. My Libre Sensor said 6.4 (but that's a proxy so I understand that it will be different to glucometer reading). My Contour Next said 6.8. My FreeStyle Optium said 6.7. So they're all pretty close to each other and within the published margin of error. I'm happy anyway

Edit: In case anyone wonders, I have the FreeStyle Optium mainly/only because it can do ketone tests as well and my educator wanted me to be able to measure ketones (currently 0.2 but I have no idea what that means). For blood glucose I prefer the Contour Next because the strips seem to draw the blood up much more easily than the FreeStyle which seems to want a lot more blood than the Contour. But that's just a personal preference and might be related to my technique, I'm not sure, and not related to accuracy
 
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biren1973

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Type 2
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Thanks for all your comments. Mine is around 20% difference.

This morning I tested with my old one which is GlucoNavi, the figure coming as 6.1, however with my new machine GlucoRx it comes as 7.3 a difference of 1.2 which I think is lot

Regards
 
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chrisjohnh

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285
Type of diabetes
Type 2
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Diet only
Thanks for all your comments. Mine is around 20% difference.

This morning I tested with my old one which is GlucoNavi, the figure coming as 6.1, however with my new machine GlucoRx it comes as 7.3 a difference of 1.2 which I think is lot

Regards
I also use a GlucoRx Nexus Blue and am always consistent in preparation for its use. Because of the variability I take at least 2 and sometimes up to 4 readings on each occasion and treat their average as “the result”. The typical deviation with my meter is about 0.6 but sometimes up to 1.0.
 
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biren1973

Well-Known Member
Messages
119
Type of diabetes
Type 2
Treatment type
Tablets (oral)
I also use a GlucoRx Nexus Blue and am always consistent in preparation for its use. Because of the variability I take at least 2 and sometimes up to 4 readings on each occasion and treat their average as “the result”. The typical deviation with my meter is about 0.6 but sometimes up to 1.0.
Oh really, difference of 1 is still lot. Difficult to trust which one is giving correct results.

Anyone know what brand does GP use? I can't remember when I visited them last time.

Regards
 
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catinahat

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Oh really, difference of 1 is still lot. Difficult to trust which one is giving correct results.

Anyone know what brand does GP use? I can't remember when I visited them last time
The one your GP uses has the same accuracy, if you were to take both of your meters to the Dr and do. 3 tests, one with each of your meters and the Dr's, you would have 3 different results. All the results would be within the 15% plus or minus range of your actual glucose level.
Which of the three are the closest to your true level is impossible to know, not even your doctor would have the faintest idea. And of course if it were possible to know for sure your true sugar level and you repeated the three meter experiment, it would probably be a different one of the three that was closest second time around.
The only way to get a truly accurate sugar level is to have a sample tested in a lab, by the time you got the results back your levels would have changed. Then you would have accurate but totally irrelevant information.
The accuracy of the meters is not ideal, we would all love them to be more accurate but its what we've got and better than nothing.
 
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catinahat

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the figure coming as 6.1, however with my new machine GlucoRx it comes as 7.3 a difference of 1.2 which I think is lot
+/- 15% of a 6 mmol result =7.06 and 5.1
+/- 15% of a 7 mmol result =8.2. and 5.9

You can see that if your true level was for example 6.5 then the results from both of them is within the 15%

The 15% is the possible variance between any meter and your actual sugar level, not the difference between your 2 meters. One could be 15% high the other 15% low so the difference in your results could be 30% and their manufacturers would argue that both are within range.

Using two meters is never a good idea, it just leads to confusion and doubt. My advice would be to pick the one you like best and put the other one away, keep it as a spare.

When we test we don't need to know our level down to a decimal point, the difference between 6 and 6.2 is probably just one grain of sugar. If our meters show a 6 before we eat and 10 after we know that meal was too carby. If we get a 7 after we know our sugar's are more or less in the same range as before and that meal was perfect.
 

Monica_JJ

Member
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7
Type of diabetes
Type 2
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Tablets (oral)
As per @catinahat & other replies.
The meters aren't entirely accurate...none of them are .

I read up when first on scene, & while I understand the need for pinpoint accuracy, I doubt any ever could offer that .

And given that many things can raise our BG, infections/illness being just one, it's a constant game of reading between the lines & deciding what is causing any recent rises (or lowerings )

The best I think we can hope for is a trend of numbers up or down to guide & help keep us safe.

I likened not knowing our testing numbers to being in a long corridor, In the dark trying not to hit the walls or trip over as we fumble our way along it.

The meter just shines a light so we know when we are close to the walls, and in danger of bumps & bruises ...aka making us stop & consider what might be causing it and what to avoid/ prepare for

If we follow the light (numbers) we can likely avoid too many hits over the forthcoming years .

Well, that's how I see it.

Others may have a different view .
I like your analogy so much, it's really apt!!
 
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jjraak

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I like your analogy so much, it's really apt!!
Thank you @Monica_JJ .

It was influenced by my feelings at DX.

Practically told on way out of appointment for something else I was having blood tests for.

The gloom that descended on me once home & googling type 2 ..<gulp>

Left stumbling around in the dark really until I found this forum, and all the lovely people offering first hand advice of how to cope, eat & manage T2D.

So, yes I think you are right.
It is rather apt.