Certified Diabetes Educator Practice Exam 2026 - Free Practice Questions and Study Resource.

Blood glucose meters are primarily calibrated to plasma values due to the higher concentration of glucose found in plasma compared to whole blood. This calibration reflects standard laboratory practices, where glucose measurements are typically made on plasma rather than whole blood. Plasma contains a higher volume of water, which dilutes the glucose concentration compared to whole blood.

By calibrating to plasma, blood glucose meters can provide readings that are more accurate and comparable to those obtained in a clinical lab setting, allowing for better management of diabetes based on consistent and precise measurements. The calibration towards plasma also aligns with treatment guidelines and helps to ensure the glucose levels that patients monitor at home are clinically relevant.

In contrast, whole blood measurements can lead to variability due to factors like hematocrit levels, which affects the proportion of cells to plasma in the blood sample. The calibration to specific types of blood, such as serum or capillary blood, is not standard for most meters when providing user-friendly readings for diabetes management.