User Manual

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 Comparing Monitor and Laboratory Results
The result you obtain from your monitor may differ somewhat from your
laboratory result due to normal variation. Monitor results can be affected by
factors and conditions that do not affect laboratory results in the same way
(See test strip package insert for typical accuracy and precision data and for
important information on limitations). To make an accurate comparison
between monitor and laboratory results, follow the guidelines below.
Before you go to the lab:
Perform a control solution test to make sure that the monitor is working
properly.
It is best to fast for at least eight hours before doing comparison tests.
Take your monitor with you to the lab.
While at the lab:
Make sure that the samples for both tests (the monitor test and the lab test) are
taken and tested within 15 minutes of each other.
Wash your hands before obtaining a blood sample.
Never use your monitor with blood that has been collected in a gray-top test
tube.
Use fresh capillary blood only.
You may still have a variation from the result because blood glucose levels can
change significantly over short periods, especially if you have recently eaten,
exercised, taken medication, or experienced stress*
6
. In addition, if you have
eaten recently, the blood glucose level from a finger stick 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*
7
.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 (severe dehydration) may also
cause a monitor result to be different from a laboratory result.
References
*6: Surwit, R.S., and Feinglos, M.N.: Diabetes Forecast (1988), April, 49-51.
*7: Sacks, D.B.: “Carbohydrates. “ Burtis, C.A., and Ashwood, E.R.( ed.), Tietz
Textbook of Clinical Chemistry. Philadelphia: W.B. Saunders Company (1994),
959.
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