At my local nuffield hospital, I had a blood test where blood was drawn from my left mid arm. This was to give me a comparison value to measure my blood glucose against. At home, especially after warming up my hands to the point of them turning red, my fasting glucose is considerably higher. This has me scared as I don't know which results are the truth.
Arm: 5.1
Home: 6.9
How accurate are the arm blood tests?
Edit: Forgot to say I have Raynaud's. Will this affect my results from the arm as much as my hands?
The reality is, about the only way to roughly compare would be to sit in the phlebotomy room, allow your venous blood to be drawn, then immediately prick your finger, but even that will only be approximately the same.
Venous and capillary blood differ, in that it can take a while for blood to get from the veins to capillaries. Add in there anything that happens along the way, in terms of stress, eating, drinking, even water and all can influence what your meter returns.
I differ from you in that venous draws are alway higher than my finger prick testing, and even if I average it all out, my finger prick estimated A1c scores never, ever have matched lab levels.
After almost six and a half years, I accept this now, and view the two reading as different.
Having been living with diabetes, I now appreciate that's provided my finger prick scores are between x and y number, my A1c scores are likely to be good. I won't state those numbers as everyone is different in terms of their desirable zones. This is something you have to work out form yourself.
In saying that, I am not trying to be unhelpful, but for me to suggest you need to be between x or y could be completely wrong for you, and as such, unhelpful.
My advice to you would be to run a diary of blood glucose finger prick readings, alongside exactly what you have eaten, recording times alongside all of it, and also recorded how you felt.
Over a period, that will help you understand your own body.
If you need progress resorts for yourself, you can review your numbers for trends, and maybe where you see undesirably high numbers, but you could also do an interim A1c at 6-8 weeks to see the direction of travel of our your numbers.
There are a number of organisations offering A1c (and lots of other tests), which can be done at home, or in clinics, if your GP resists a short term test. Many do.