I have never actually cared what my A1C number said when results came back from the lab. And this all started when I was a child and learn about variability. Ok, it may have been conveyed in a slightly different form.
As a kid, it was really quite easy to fake a good A1C by having a lot of variability in the numbers. For reference of variability, I would run 30-50 miles per week and could easily polish off an entire pizza by myself. As I got older, my A1C went up and unfortunately, the results of A1C became of little value to me. Over the past 20 years, what is considered a “normal” A1C for diabetics has changed up and down so many times that I made up my own system for determining how good I am doing.
First, we need to have a few baselines: my target BG is 115, I do not correct a BG below 180, my acceptable range is 75-190. Additionally, every BG usually has Carbs on Board, Insulin on Board, or Exercise on Board (BGs trending up or down) – so a correction (or asterisks) of the number is necessary, since the number on the meter may no longer tell the story.
Once you have this set I can find the number of highs, lows, avg, standard deviations, and how many of them have an asterisk next to it – with an additional story. If you take a look at a “good” A1C and find a lot of highs and lows in your adjustment, the A1C is not accurate. However, if I have an “ok” A1C and have few highs and lows, and my average is acceptable – I am far better off health wise and tend to ignore the A1C result altogether.
Nb. I am not advising against getting your A1C checked – as huge swings in your A1C can be problematic of a greater issue.
How are you determining / tracking Carbs on Board? I have not heard of that before.
Same idea as insulin on board — except that it changes depending upon what you eat (combos of carbs, sugar, fat, etc) will have different lengths of time working in your system. Some foods work in a straight line, some foods have a long tail (pizza, is 85% carbs upfront, then the remaining over the next few hours), others like a buttery corn muffin will act like a mild bump in carbs for a while, then having about 50% of the carbs hit you like a brick over the course of the next 3-4 hours.
Basically, I liked the idea of Insulin on Board, it made sense to me — since it was easily quantifiable. So I took it a step further and figured out how long certain foods I eat regularly stay in my system — basically it mean that I created a system so I have no need to correct an out of range BG if I have IOB and COB that cancel out each other to get to my target (115), regardless if I am high or low.