HbA1c diagnostic criterion requires the value to be met on how many occasions?

• A. On two occasions
• B. On three occasions
• C. On a single occasion
• D. On four occasions

Answer: (A)

HbA1c reflects the average blood glucose over about the past 2–3 months, so a single elevated value could be due to lab variability or a temporary factor affecting red blood cells. To confirm diabetes, the abnormal HbA1c result must be observed on two separate occasions. When both measurements meet or exceed the diagnostic threshold (commonly 6.5% or higher), diabetes is diagnosed. If only one reading is elevated, the diagnosis is not confirmed and a repeat test or another diagnostic method is used. This safeguards against false positives by ensuring the hyperglycemia is persistent.