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SD Codefree test solutions

sanguine

sanguine

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Has anyone else used these? I bought some a month or two ago thinking they might represent a 'standard' solution of known mmol/l value, but it seems they only represent a range ('M' in my case). On one batch of strips I tested 5 and they came out in the 6.1-6.2 range. I opened a new batch this morning and three of them were 7.1, 7.1 and 6.8. I know the solution has to be discarded after 90 days, and it is warmer, but these results don't exactly fill you with confidence about the meter as a whole.

I've asked before but never got an answer, but is there a means of making a standard solution (or a set for different values) at home - something like "dissolve x grams of refined sugar in 1 litre of water, seal and keep in fridge"?
 
A suggestion, Next time you have a Fasting Blood test-Blood Drawn, why don't you test a Drop at the same time.
You will then have a very good idea of how your meter is over/under reading ?

I would be interested to see what people say on your above suggestion, but I think to get accurate measures of a Gram/litre at home would be a lucky happening, and I think normal sugar varies in purity ?
 
Thanks Randburg

I'll do that, although with the accuracy statistics of the meter you'd not get an exact comparison unless you did several tests at that time.

As for the 'recipe', yes I was being a bit flippant - but is there any product with a reliable sugar content that could be used as a 'standard'?
 
Not aware of anything that would be a constant sugar content.
The only ones I think of are test solutions, and they cover a range as you lnow
 
I know why you are asking this question. ;) I would be inclined to visit a pharmacy whilst fasting and ask for a test, then compare to your own as soon as possible before and after the pharmacy, several fingers and several tests. Maybe even ask the pharmacy to do 2 tests - or visit 2 pharmacies. It's worth a try. Other than that, if you have lost confidence in your strips/meter, try buying a new one. Just a thought.
 
Randburg said:
Not aware of anything that would be a constant sugar content.
The only ones I think of are test solutions, and they cover a range as you lnow
Click to expand...

I made enquiries of Abbott about their test solution and got this reply.

"Each 4.0 ml vial of Abbott FreeStyle glucose control solution contains:- D-Glucose* ( Low 0.05%; High 0.3%), preservative, FD&C red dye, viscosity-adjusting agent.

* D- Glucose is also referred to as dextrose."

It turns out that the solution has to be quite accurate and it is the strip and meter which have to be within a certain tolerance of it.

Another poster and myself did some sums and found that these concentrations equalled (from memory), 3.8 and 16.7.
 
Bluetit1802 said:
I know why you are asking this question. ;)
Click to expand...

Not just that LOL!

If you buy (say) a pH meter, you get standard solutions of known and accurate value to calibrate it with. Without knowing the concentration of the SD solution it seems to be a bit redundant. Maybe I should email them and ask for more info as Squire Fullwood did for Abbott.
 
I also own an SD Codefree (cheapskate) but mine has a dummy strip which you just plug in and the screen says "OK". How accurate is that?
 
Squire Fulwood said:
I also own an SD Codefree (cheapskate) but mine has a dummy strip which you just plug in and the screen says "OK". How accurate is that?
Click to expand...

Great isn't it - just to check the circuitry I guess, might just as well use a 3A fuse.
 
And this is what Home Health UK had to say

Glucose testing is subject to a variety of factors which affect the reading and as such the international accuracy requirements are for the results to be within 20% of the actual figure. Therefore, when testing with a known solution, the result needs to be within a range of values to prove the accuracy. As long as the results you have are within the range printed on the tubs then both the meter and the strips are working correctly and accurately.

Very helpful - not. So what is the value of the known solution? (chasing up).
 
You think that's not helpful? You should see what is the opinion of Roche.

"Thank you for contacting Accu-Chek.

Please be aware that performing a control test in your home environment cannot by compared to performing a control test in a laboratory, as the strict laboratory testing conditions are not met in the home environment. This means that achieving the target reading of 6.67 mmol/l is not possible. Due to these factors a target range has instead been calculated. This range takes into consideration the effects of temperature deviations and possible sources of contamination. The specific target range for the Accu-Chek Compact Plus control solution is printed on the peel-off label attached to the drum container.

Please see below important information about performing the control solution test:

Treating the control solution properly:
The solution is filled into the bottle under microbiologically controlled (low germ) conditions. To avoid contaminating the solution, do not touch the tip of the bottle with your fingers, the test strips or the surface onto which you apply the control solution. Contaminated control solution can produce incorrect results.
Use only control solution that is within its expiry date. Expired control solution can produce incorrect results. The expiry date is printed on the bottle.
Store the control solution between +2 and +30°C. Control solution that is stored outside this range may become unusable before it reaches its expiry date.
If you store and handle the control solution properly, it will remain stable for 2 months after opening. However, do not use control solution that is past its expiry date, which is printed on the bottle.
The control solution must be at the ambient temperature when you perform a control test. If you keep the control solution in a refrigerator, leave it to stand at ambient temperature before you perform a control test. Cold control solution can produce incorrect results.

Please also note:
Reproducibility (day-to-day imprecision)
The mean imprecision is < 2%. In a typical series of tests a standard deviation of 0.15 mmol/l was obtained with a glucose concentration of 8.6 mmol/l.
Calibration
The system (meter and test strips) is calibrated with venous blood containing various glucose concentrations. The reference values are obtained using the hexokinase method. This reference method is traceable to a NIST standard by means of the ID-GCMS method, the method with the highest metrological quality."

Enjoy
 
Haha yes I skimmed that in 10 minutes. So apart from trends (which are very important) we're basically bu$$ered for accuracy.
 
sanguine said:
And this is what Home Health UK had to say

Glucose testing is subject to a variety of factors which affect the reading and as such the international accuracy requirements are for the results to be within 20% of the actual figure. Therefore, when testing with a known solution, the result needs to be within a range of values to prove the accuracy. As long as the results you have are within the range printed on the tubs then both the meter and the strips are working correctly and accurately.

Very helpful - not. So what is the value of the known solution? (chasing up).
Click to expand...

"The control solution will have slight variances between each bottle so it is impossible to say the exact level for each individual bottle. "
 
sanguine said:
. Therefore, when testing with a known solution,
Click to expand...

So now the known solution varies from bottle to bottle?

Home Health UK (Barry) tried to snow me as well. They sent me copies of the Zurich research and said it proved everything was OK>
 
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