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SD Codefree giving high readings?

Bluetit1802 said:
According to the info in that converter tool you refer to, if your meter is calibrated to convert to plasma, there is no need to do any conversion. The Codefree is calibrated to be "plasma equivalent" .
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Using the converter or simply going from my recorded meter average, neither are close to my venous HbA1c scores.
 
Bluetit1802 said:
According to the info in that converter tool you refer to, if your meter is calibrated to convert to plasma, there is no need to do any conversion. The Codefree is calibrated to be "plasma equivalent" .
Click to expand...
Sorry, but the plasma refers to bgl conversion of venous blood that only applies on the day the blood was taken so it is the lab equivalent of the finger prick test, but more accurate. The HbA1c test uses the same blood sample, but will give a different result that is not equivalent to your meter reading. Plasma is a daily result, HbA1c is a 3 month average value. The lab plasma result is not generally reported back unless the GP specifically requests it.
 
Oldvatr said:
The SD is hard calibrated in the meter itself, but Accuchek changed their strips to make the transition to plasma 'truly codefree' so it will not be in the Accuchek leaflet for the meter. Their website confirms this strip change since 2011. No changes to meter hardware was required.
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In my Accu Chek mobile meter booklet (updated January 2012)

"Although you always apply whole blood to the test area, the blood glucose results displayed by your meter correspond to those in plasma"
 
AndBreathe said:
Surely what it reads is what it reads, for T2? OK, there have been the odd glitch where a batch of strips have been a bit "odd", but what is anyone actually going to do, on a day to day basis if you're meter says 4.9 and venous blood would have you at 4.5 or 4.9, or whatever?

I can see that it could be more important for T1s, or those taking potentially hypo inducing medication, but those individuals should having their meters and strips prescribed, which is very unlikely to be the Codefree.

My Codefree meter readings, when converted, using the usual converter tools, such as on this site, are never that close to the venous tests the lab analyses. That said, nor are the venous tests close to my Libre averages, which are usually lower than my Codefree readings.

When I swap from one batch (as opposed to each pot) to another, I usually do 2 or 3 comparative tests, then I just go with the flow, but then I'm really concentrating on my trends and my return to baseline times.

Maybe I just over simplify things, but it works for me.
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Simples. If you are a driver then DVLA recommends that you do not drive with bgl less than 5.0 mmol/l. so at 4.9 you should not drive. If you do, and have an accident, and it was shown that your test was 4,9 then your insurance would be invalidated, and you could be faced with criminal negligence claims. Remember that the meter records both time of test and value, so a read of the memory would give this info. For this reason, I do not set the clock to current time or date.

The other reason I query your assertion regarding T2D, I have had instances when my NEO reads 3.9 or less, but my SD reads over 5 mmol/l/ Thus if I was relying on my SD only, then I would not register a hypo, even though my NEO is flashing red at me. If I was hypo unaware, then this could be dangerous. As it happens, I do get other symptoms. However, my hypo's do tend to be quite benign due to ketosis, so I have ample time to react. I am on Gliclazide, so am prone to hypo when on low carb diet. For others this may not be such a low key event.
 
Bluetit1802 said:
Kevin, do you find this with every tub of Codefree from all batches, or just certain tubs from different batch numbers?
I find some tubs/some batch numbers read virtually the same as my Accu Chek Mobile, whilst others differ.
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Yes I do. Always around 1.0 mmol +


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Oldvatr said:
Simples. If you are a driver then DVLA recommends that you do not drive with bgl less than 5.0 mmol/l. so at 4.9 you should not drive. If you do, and have an accident, and it was shown that your test was 4,9 then your insurance would be invalidated, and you could be faced with criminal negligence claims. Remember that the meter records both time of test and value, so a read of the memory would give this info. For this reason, I do not set the clock to current time or date.

The other reason I query your assertion regarding T2D, I have had instances when my NEO reads 3.9 or less, but my SD reads over 5 mmol/l/ Thus if I was relying on my SD only, then I would not register a hypo, even though my NEO is flashing red at me. If I was hypo unaware, then this could be dangerous. As it happens, I do get other symptoms. However, my hypo's do tend to be quite benign due to ketosis, so I have ample time to react. I am on Gliclazide, so am prone to hypo when on low carb diet. For others this may not be such a low key event.
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Could you show me the DVLA Guidance where someone taking no medication must be 5 to drive? That's a genuine request, because that being the case, I can only drive at around an hour after a decent meal, including carbs.
 
AndBreathe said:
Could you show me the DVLA Guidance where someone taking no medication must be 5 to drive? That's a genuine request, because that being the case, I can only drive at around an hour after a decent meal, including carbs.
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https://www.gov.uk/government/publications/information-for-drivers-with-diabetes
http://www.diabetes.co.uk/driving-and-hypoglycaemia.html

What is not covered is what is termed pre-existing condition. Even though you are not on medication, the diagnosis of diabetes must be given to your insurance company, who could withold insurance if you did not declare it. Similarly, when they get hold of medical records following an incident, then they could use this against you. So although DVLA no longer provide the guidance they used to, the insurance companies are desperate to find wriggle room to avoid meeting claims. You should be ok provided you tell the insurance.
 
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Oldvatr said:
Sorry, but the plasma refers to bgl conversion of venous blood that only applies on the day the blood was taken so it is the lab equivalent of the finger prick test, but more accurate. The HbA1c test uses the same blood sample, but will give a different result that is not equivalent to your meter reading. Plasma is a daily result, HbA1c is a 3 month average value. The lab plasma result is not generally reported back unless the GP specifically requests it.
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Thank you. If you are trying to tell me the difference between snapshot venous tests and HbA1c tests, I am well aware of how each of them work. If you are trying to tell me something else, I'm not sure what that is. I was simply referring to the converter from whole blood to plasma blood (on this website) and the 12% discrepancy between plasma and whole. If our meter is calibrated for plasma equivalent, it is of no use using the converter tool.

http://www.diabetes.co.uk/whole-blood-readings-to-plasma-converter.html
 
I binned my SD Codefree meter because the readings were so incorrect all the time.

Based on what the Codefree was telling me my HbA1c would be over 50


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Bluetit1802 said:
Thank you. If you are trying to tell me the difference between snapshot venous tests and HbA1c tests, I am well aware of how each of them work. If you are trying to tell me something else, I'm not sure what that is. I was simply referring to the converter from whole blood to plasma blood (on this website) and the 12% discrepancy between plasma and whole. If our meter is calibrated for plasma equivalent, it is of no use using the converter tool.

http://www.diabetes.co.uk/whole-blood-readings-to-plasma-converter.html
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Thank you for bringing this to my attention. I thought you were referring to the converter of average meter readings to HbA1c.

You are correct. The SD and Acccuchecks do not need to be adjusted for plasma. There may be other makes that this also applies to, but so far no one has identified any. My surprise is complete since I had previously requested this very tool to be added to this website, but no one has told me it has arrived. Thanks for putting up the link so others can use it. This was a recurring thread theme that keeps returning. Now we have an answer for it.
 
britishpub said:
I binned my SD Codefree meter because the readings were so incorrect all the time.

Based on what the Codefree was telling me my HbA1c would be over 50


Sent from my iPhone using DCUK Forum mobile app
Click to expand...

That is a shame. My Codefree meter is fine for one such as I, diet only. I also have an Accu Chek Mobile and do comparisons when I receive a new batch number of Codefree strips. The difference appears to be insignificant. I am the opposite to you in that my HbA1c is always much higher than my Codefree averages indicate. Before I get a lecture on catching peaks - I do catch my peaks by testing several times after meals, all meals most days. I also use a Libre Sensor from time to time, and this confirms I am catching my peaks.

I just have to accept that my HbA1c is higher than expected because I happen to be a high glycator. Equally, some people may see an HbA1c lower than expected if they happen to be a low glycator. Not a lot I can do about that.
 
Oldvatr said:
Here is what I discovered when I first got my SD Codefree
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I wonder if one reason for these differences is because the BG readings were high? Have you a similar graph showing differences when BG readings are at the normal end? Most of my readings are 5s and 6s .
 
Bluetit1802 said:
I wonder if one reason for these differences is because the BG readings were high? Have you a similar graph showing differences when BG readings are at the normal end? Most of my readings are 5s and 6s .
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No I have not analysed the error at 'normal levels' but I do still get them as significant. I can show my last 4 days readings per ex:
SD / NEO / DIFF / %ERR
5.3 / 3.9 / 1.4 / 26.4
5.7 / 4.4 / 1.3 / 22.8
6.1 / 4.8 / 1.3 / 21.3
6.8 / 4.6 / 2.2 / 32.3
So you can see it is diabolical at near hypo levels. Note: i have not adjusted for Plasma on any of these comparisons since at the time I did my review I was not aware of that. I have shared my personal journey in a thread of that name which also shows the two meters track each other when averaged so I can use the SD with care. and the strips are so much cheaper.

EDIT sorry, website strips formatting chars.
 
Oldvatr said:
https://www.gov.uk/government/publications/information-for-drivers-with-diabetes
http://www.diabetes.co.uk/driving-and-hypoglycaemia.html

What is not covered is what is termed pre-existing condition. Even though you are not on medication, the diagnosis of diabetes must be given to your insurance company, who could withold insurance if you did not declare it. Similarly, when they get hold of medical records following an incident, then they could use this against you. So although DVLA no longer provide the guidance they used to, the insurance companies are desperate to find wriggle room to avoid meeting claims. You should be ok provided you tell the insurance.
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OK, so we'll agree 5 to drive for someone on diet only (never mind that my diabetes is recorded on my medical records as "Diabetes Resolved") is an irrelevance for me, for driving, provided my insurers are aware of my medical history?

Just clarifying for anyone unsure what they should be doing in similar circumstances.
 
AndBreathe said:
OK, so we'll agree 5 to drive for someone on diet only (never mind that my diabetes is recorded on my medical records as "Diabetes Resolved") is an irrelevance for me, for driving, provided my insurers are aware of my medical history?

Just clarifying for anyone unsure what they should be doing in similar circumstances.
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When I had problems getting test strips from GP it was one aspect I used to get coverage for extra strips. However I did tick the Gliclazide box as well, so it was a no contest when NICE changed their guidelines. I use 5 as a working limit and test before driving so that I would have the backup if I need it. It also reduces the journeys made by Dads Taxi. As you say this level is high for someone controlling by diet only but if you take into account the accuracy difficulties with meters then that 5.0 on an SD or Accuchek could be as low as 3.57 mmol/l and still be meeting the ISO for the meter (worst case error), so it is not that far out.
 
Oldvatr said:
When I had problems getting test strips from GP it was one aspect I used to get coverage for extra strips. However I did tick the Gliclazide box as well, so it was a no contest when NICE changed their guidelines. I use 5 as a working limit and test before driving so that I would have the backup if I need it. It also reduces the journeys made by Dads Taxi. As you say this level is high for someone controlling by diet only but if you take into account the accuracy difficulties with meters then that 5.0 on an SD or Accuchek could be as low as 3.57 mmol/l and still be meeting the ISO for the meter (worst case error), so it is not that far out.
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Bottom line it, if all diabetics had to be 5 to drive, there would be no need to mention insulin or other drugs in the DVLA guidance at all. Most T2s are instructed (not just advised) not to test, so potentially your 5 to drive statement could be extremely alarming to a new person, who also drives. If it hasn't been mentioned, or if they've been told not to self test, they could feel like they were playing driving license Russian Roulette every time they sat behind the wheel of a motor car, or sat astride their motorcycle/moped.

I have to say in applying for motor insurance, I have never experienced any iota of interest from the Company, but as you say, it's always important to disclose fully.

I will just for completeness say that nobody, irrespective of their diabetes status should drive if they feel unwell in anyway.
 
Maybe the wrong place to ask but if people are disputing the results of the SD Codefree what is the next most cost effective solution? Realistically the strips are costing me around 13p each - the one from the Doc's had strips at around 35p. When you are testing 6/7 times a day it soon adds up!

I have better things to spend money on than blood testing strips ;)
 
AndBreathe said:
Bottom line it, if all diabetics had to be 5 to drive, there would be no need to mention insulin or other drugs in the DVLA guidance at all. Most T2s are instructed (not just advised) not to test, so potentially your 5 to drive statement could be extremely alarming to a new person, who also drives. If it hasn't been mentioned, or if they've been told not to self test, they could feel like they were playing driving license Russian Roulette every time they sat behind the wheel of a motor car, or sat astride their motorcycle/moped.

I have to say in applying for motor insurance, I have never experienced any iota of interest from the Company, but as you say, it's always important to disclose fully.

I will just for completeness say that nobody, irrespective of their diabetes status should drive if they feel unwell in anyway.
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I would agree, but this is rhe advice that I remember when I was diagnosed
<< If you are on insulin, check your blood glucose within two hours before getting behind the wheel and every two hours whilst driving.

The DVLA advise that if blood glucose is 5mmol/l or less you should take carbohydrate before driving. If it is less than 4mmol/l do not drive.>>

This used to be on the DVLA website in a specific Info pamphlet, but seems to have been removed now. It does specifically relate to insulin users, and did not mention other oral meds.
 
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