A1C prick or draw?

The week I was diagnosed with gestational diabetes I went to my RCP for an A1C test. The finger prick measured 5.5. Later that day I had an OB appointment. Thrown in with my other labs was an A1C. Results (again, same day) were 5.0. I am putting that down to better accuracy with a veinous draw. Does that sound right? Or is the test just that variable?

Who knows. I suspect if you asked the providers they’d say that they both confirmed a “normal” result. I’ve tried to pin my doctors down on that very question several times and haven’t gotten anywhere. Either way, pat yourself on the back and be assured your a1c is in the healthy range, which is all that either lab can really tell you… In that context, they agree

Edit to add-- if I had to take one to the bank it would be the actual lab draw… But think within the greater context of reality, they’re both telling you the same thing.


Thanks, Sam. I was confused by that. I wish I could pat myself on the back. I think I really lucked out getting diagnosed when I did–so early in the process. Maybe I can pat myself on the back at my next A1C if I’ve managed to keep it low. I’ve been trying so hard, but with Clarity chronically underprojecting the A1C, I’m not totally confident I’ll be able to pull it off.

I guess part of me is still trying to discern where I am in this weird progression. Honeymoon? Sort of. I do require insulin, but maybe not as much as I will need down the road:? Hard to project, but I get nervous thinking about numbers climbing along with disease progression. Or is the numeric climb something that can be controlled with vigilance? I’m thinking here of DrBB’s recent post about bs hanging out high for days with one beer and no cake. Yikes!

All A1C tests have a +/- 0.5% variance. Thus, a 5.5% A1C could be 5.0% or 6.0%. Key is to stay with one method, with one lab or doctor. They usually run roughly the same.

For example, my doctor’s office does a finger stick and always runs 0.3% lower than my normal lab does.

The current standard for certified labs is that they must perform the HbA1c within +/- 6%. This means that a lab test with an A1c result of 5% is likely between 4.7% and 5.3%. Unfortunately A1c tests such as the A1cNow which are used in doctors offices are not so accurate. While they are certified by the NGSP to meet documentation and other requirements they are not evaluated for accuracy like the +/-6% that is associated with a Level 1 Lab. In general you should place much more faith in the lab reading.

Not sure what post that was but I certainly hope I didn’t say something that would lead you to despair of being able to handle this! :slight_smile: I have been known to post on the ever-popular subject of “I just don’t GET this!” I think those situations mainly demonstrate one of the fundamental principles of T1 care: Sometimes Weird Sh** Just Happens. I’ve definitely had stubborn highs that I couldn’t easily account for, but it’s not a chronic thing. I’ve been at this for 33 years, still no major complications and my most recent A1c was 6.1.