If diabetes is suspected on the basis of the symptoms above, blood sugar should be tested immediately using a blood sugar meter. A single random measurement of over 11 mmol/L is strong evidence of diabetes. In children particularly, a random blood glucose sample may be more useful than a fasting one. Children have limited glycogen stores, and a child who is hyperglycaemic during the day may have a near-normal blood sugar first thing in the morning.
In the event that blood testing is impractical, stick testing of urine for glucose should be performed - the finding of glycosuria in this context justifies a presumptive diagnosis of diabetes, whereas the absence of glycosuria makes the diagnosis very unlikely. Stick testing also allows evaluation of ketonuria, which indicates impending decompensation and may inform the urgency of further referral.