Fora V30a Read Before Use page 53

You may still have a variation from the result because blood glucose
levels can change significantly over short periods of time, especially if
you have recently eaten, exercised, taken medication or experienced
*2
stress . In addition, if you have eaten recently, the blood glucose level
from a finger prick can be up to 70 mg/dL (3.9 mmol/L) higher than
blood drawn from a vein (venous sample) used for a lab test
Therefore, it is best to fast for eight hours before doing comparison
tests. Factors such as the amount of red blood cells in the blood (a
high or low hematocrit) or the loss of body fluid (dehydration) may also
cause a meter result to be different from a laboratory result.
References:
*2: Surwit, R.S., and Feinglos, M.N.: Diabetes Forecast (1988), April, 49-51.
*3: Sacks, D.B.: " Carbohydrates. " Burtis, C.A., and Ashwood, E.R.( ed.), Tietz
Textbook of Clinical Chemistry. Philadelphia: W.B. Saunders Company (1994),
959.
*3
.
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