When you get 2 different BG readings which do you trust?

[James_Donnelly]

So, which do you go with when you get two different blood glucose readings when you get wo different readings depending on which finger you test? This is such a frustrating thing. Especially when it's hypo range.

For example, right now I just measured the ring and index fingers on my right hand. Ring finger gave me 3.6, index gave me 4.4. I then went and washed my hands, came back and measured the two fingers again. This time the ring finger gives me 4.1 and the index gives me a bloody 3.5 ugh

So frustrating because the difference between these numbers is important. If I am 4.4 I am fine but if I am 3.5 then I need to take action. Annoying this is I feel fine because I have less hypo awareness these days.

Which to trust. I'm just going to have a snack (10g carbs) and be on the safe side.

 

[evilclive]

Even 4.4 is an excuse for something small and tasty IMO. They all average out at 4-ish, so I'd just use that excuse.

 

[karen8967]

i would say somewhere in the middle of both readings but im no expert this is just what i do

 

[therower]

@James_Donnelly. Well I suppose you could go for the average reading of 3.9.
It is frustrating, but all to common for different fingers giving different readings each and every time we use them.
Information overload.
On a personal level I would use the first reading only and decide that I was in the low zone. The only time I test twice is if a reading just doesn’t tally with how I feel within myself.
I can be easy to become paranoid with readings that in all reality are never going to be completely accurate or identical at any one given time.

 

[Scott-C]

I tend to think in terms of ranges instead of absolute numbers.

Meters aren't all that accurate, and, even if they were, I'm not convinced that concentration of glucose is evenly distributed in blood - capillaries, arterioles etc are such an incredibly complex plumbing system, it would be a surprise if bg taken from one finger was actually the same as bg taken from another.

I'd view all the test results as being generally in the 3.5 to 4.5 range, which is enough for me to be reasonably certain that it's not in, for example, the 6 to 9, or 9 to 13 range, and, even though I don't know in absolute terms whether the number is a low 3.5 or a decent 4.5, there's still enough information there to give me a heads up on whether I should be thinking about having a biccie or not, or the less exciting option of a 3g glucotab.

T2s especially need to get their heads round the realities of bg measurement. It pains me when they pain themselves getting wound up about a difference between 5.3 and 5.9 - those are the same number. A lot of T2 philosophy is based on failing to understand the limitations of bg measurement.

Still, having said all that, I do still get a kick out of my cgm showing a delta of 0.05 since the last read!

 

[Jaylee]

Hi,

Weeeell!?
As an insulin user that index digit could read 3.5. So I treat & 10 minutes later it could be 2.5? (Aprox numbers off the top of my head.)
The point is (as @Scott-C points out a complex bit of plumbing more complex than a jap import coolant system. )
This is where folk panic thinking the carbs ain't working..
The meter reading is also like a "snaphot in time" upto 20 minutes ago? So the "2.5" I mentioned ten minutes after 15g of carb hitting my digestive system would be how low I dropped (aprox.) before I treated due to that delay, or time lag...The 3.5 upto 30 minutes prior, was the warning..

If your low? Shoot first, ask the questions later.. IOB can do anything.
(Just read back what I wrote & it looks like a script from Doctor Who. But you get the gyst.)

 

[Scott-C]

complex bit of plumbing more complex than a jap import coolant system.

Jay, at some point in the next few years, the DAFNE people are going to ask you to write a chapter explaining T1 biology in terms of analogies with Japanese import vans.

You've found your niche - DKA is a full Nanatomi 5R fuel tank but no Rioki 20 spark plugs to burn the fuel!

 

[Bluey1]

Are you hypo aware? If so trust your feelings. With 2 different meters I managed to get one saying Hi and the other Lo from the same blood sample. That is a rarity and should never happen and I think one of the strips was off - before anyone points it out all strips were in date and properly cared for. I went for a 2nd opinion as I had checked and I felt very Hypo (after another set of tests I was Hypo around 2 ish mmol/l.

I then ran a test over a few weeks, Libre and Enlite (I had 1 Libre left over) and 3 brands of meters.
It was common of 2.1mmol difference between the lowest and the highest meters, rare for all 3 to be less than 1.0mmol/l and rare for over 4.0mmol/l difference

Go with how you feel as these things are only a guide. If you feel OK and your meter is 3.5, keep going as per normal, just keep something on hand if required.

These meters are only to be used as a guide, not an accurate reading

All countries have slightly different accuracy requirements. but roughly 99 out of every 100 readings the meter / strips should be +/- 15%, the other 5 readings anything goes.

Assume with you first test the actual number was 4.2 the meters could read 4.8 to 3.6 mmol/l and still be considered accurate.

One example of accuracy for Australia - I used this in the example above.
https://www.diabetesqld.org.au/media-centre/2017/may/how-accurate-is-your-blood-glucose-meter.aspx

 

[Jaylee]

Jay, at some point in the next few years, the DAFNE people are going to ask you to write a chapter explaining T1 biology in terms of analogies with Japanese import vans.

You've found your niche - DKA is a full Nanatomi 5R fuel tank but no Rioki 20 spark plugs to burn the fuel!

Gosh, I hope not...! If you've ever read debates on threads on flow & return & the actions of the stat in this process, improved MPG or the correct mix of veg oil to diesel ratio & how it can clog the "banjo filter."

You'll be glad you stuck with this site...

 

[Scott-C]

Gosh, I hope not...! If you've ever read debates on threads on flow & return & the actions of the stat in this process, improved MPG or the correct mix of veg oil to diesel ratio & how it can clog the "banjo filter."

You'll be glad you stuck with this site...

Lol, I'm going to steer clear of sites doing flame wars about Japanese machinery, I've got enough on my hands persuading people that a bit of lasagne isn't going to kill them...