converting meter readings to HbA1c

http://www.diabetes.co.uk/hba1c-to-bloo ... erter.html

I found this very useful tool a few weeks ago. Since I started testing and adapting my diet I have seen my levels steadily falling, and this has included a lot of tests in my highest spikes, - about 1 hour after eating. My average readings have been a higher over the last couple of days, so I was a bit concerned about what this does to the average.

I will be having another HbA1c at the end of this month, and so converted the highest of the average readings, 6.2mmol/L, as well as the lower reading of 6 on my meter using this tool and both came up with an estimated HbA1c of 6%. I am expecting something a lot closer to 6% at th e next "official" test.

Then I wondered what my average needed to be to get under 6%, so I converted 5.9% to a mmol/L reading and got 6.111111111. The result seemed to be higher than the average readings I put in :?

Is this not a straight forward conversion? There seemed to be a bit of a discrepancy in the converted readings.

What about the rest of you? Have you used this tool and how accurate was it for predicting your HbA1c?

I am doing 6-8 tests a day, sometimes more, and I'm aiming to pick up my spikes and manage my morning liver dumps a bit better. So I'm fairly confident I have the full range of my BS readings.

I know the HbA1c is an average and that a "good" HbA1c result may not pick up on some of the unacceptable spikes that cause the damage.

My question was in relation to the accuracy of the calculator on this site, because the results it gave me did not seem consistent.

When I converted my average reading of 6.2 mmol/L to an HbA1c, that reaings was 6%
When I converted 6% HbA1c to mmol/L it came out at 6.3 - higher than the number I put in to start with.
When I put in 5.9% (to establish what average I would need to get to that level) it came out at 6.1111111mmol/L
When I converted 6.11111111mmol/L back to an HbA1c, it came out at 6% :?

try it with your own numbers - do the calcualtion both ways (mmol/L to HbA1c and vice versa) and you will see what I mean about the inconsistent results. Unless it really is just me :wink: :roll:

The numbers churned out by the calcualtor appear to have a very wide margin of error. I wanted to know if anyone had used the software on this website to estimate their HbA1c and how accurate the tool on thi website is, rather than the methodology behind the HbA1c and fluctuatiuons in the BG over course of a day. Sorry if that wasn't clear in my original post.

I have not yet managed to get my meter to connect to the program that came with it, so we will see how accurate that software is when I plumb it in.

sugarless sue said:

I find that calculator confusing because if you put in a whole number in the mmol/l it converts it to a mmol/mol Hba1c!!If you put in a decimalised number it converts to an Hba1c %.

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Phew! So it is not just me.

Sid Bonkers said:

Spiral said:

When I converted my average reading of 6.2 mmol/L to an HbA1c, that reaings was 6%
When I converted 6% HbA1c to mmol/L it came out at 6.3 - higher than the number I put in to start with.
When I put in 5.9% (to establish what average I would need to get to that level) it came out at 6.1111111mmol/L
When I converted 6.11111111mmol/L back to an HbA1c, it came out at 6% :?

Click to expand...

Just to through another spanner in the works so to speak, don't forget that most meters work to a tolerance of 10% + or - so a reading of 6.0 could be out by .6 either way

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Worked that one out. I have 2 meters, the Accu-check Aviva that Roche sent me and the Contour I "won" from the competition at the top of the page. I tested at the same time from the same drop of blood - 0.4mmol/L difference :|

I plan to take them both with me when I have my next fasting test at the surgery.