aside the fact that there is high glucose concentration in the blood of a diabetic individual, is there a different in maybe rate of sedimentation or colour or what other difference can be revealed ?
There are classical but clinical signs and symptoms (polyuria, polydipsia and polyphagia) that distinguishes a diabetic from a non diabetic individuals, aside the presence or absence of glycosuria. However, since your question is directed to procedure for blood examination or test, Kazuko has hit the nail on the head and i quite agree with the researcher. OGTT is the gold standard for confirming diagnosis of DM as recommended by the World Health Organization. Other procedures such as HbA1c is to test for patient's compliance or follow up of treatments over a period of time.
OGT results often show a delayed ability to return to baseline in diabetics. the normoglycemic person should return to baseline in 2 hours or less and diabetics usually take 3 hours to return to baseline.