Page "Hypoglycemia" Paragraph 12

Blood glucose levels discussed in this article are venous plasma or serum levels measured by standard, automated glucose oxidase methods used in medical laboratories.

For clinical purposes, plasma and serum levels are similar enough to be interchangeable.

Arterial plasma or serum levels are slightly higher than venous levels, and capillary levels are typically in between.

This difference between arterial and venous levels is small in the fasting state but is amplified and can be greater than 10 % in the postprandial state.

On the other hand, whole blood glucose levels ( e. g., by fingerprick meters ) are about 10 %- 15 % lower than venous plasma levels.

Furthermore, available fingerstick glucose meters are only warranted to be accurate to within 15 % of a simultaneous laboratory value under optimal conditions, and home use in the investigation of hypoglycemia is fraught with misleading low numbers.

In other words, a meter glucose reading of 39 mg / dL could be properly obtained from a person whose laboratory serum glucose was 53 mg / dL ; even wider variations can occur with " real world " home use.