This one has a reasonably settled answer, so here it is. Quarterly for the first year is convention rather than evidence, and it is defensible for a simple reason: it is roughly the interval over which HbA1c becomes informative again, since it reflects about three months of glycaemia. After the first year, and once doses are stable, annual is reasonable unless something specific is being followed.

SarahChen_PharmD said:

Quarterly for the first year is convention rather than evidence, and it is defensible for a simple reason: it is roughly the interval over which HbA1c…

That is correct as far as it goes, and here is where it stops going. One addition: if the lab changes analytical platform between your draws, the comparison breaks and nobody tells you. It is worth asking when a value moves inexplicably.

If somebody has the primary source to hand I would rather cite it than paraphrase it.

Dr.ReproEndo said:

My prescriber ordered three tests and this board recommends about twenty, and I would like to know which of those two lists is right.

Same position here, arrived at the long way round. A defensible baseline is short: HbA1c and fasting glucose, a lipid panel with ApoB if you can get it, ALT and AST, creatinine with eGFR, TSH, ferritin and B12, and a full blood count. That set catches the things that change, the things that explain symptoms, and the things that alter the prescribing decision. Almost everything else on the long circulating lists is either invariant, uninterpretable without a specific question, or an incidental finding waiting to cause an unnecessary workup.

I would rather be corrected than agreed with, if it comes to it.

Clinical perspective, offered as context rather than as advice.

Blood work came back perfect. baseline bloodwork + this community = winning. 🏆