COMPARING METER AND LABORATORY RESULTS
The meter provides you with plasma equivalent results. The result you
obtain from your meter may differ somewhat from your laboratory result due
to normal variation. Meter 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 informa-
tion on Limitations). To make an accurate comparison between meter and
laboratory results, follow the guide-lines below.
Before you go to the lab:
˙ Perform a control solution test to make sure that the meter is working
properly.
˙ Fast for at least eight hours before doing comparison tests, if possible.
˙ Take your meter with you to the lab.
While at the lab:
Make sure that the samples for both tests (the meter 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 meter 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 of time, especially if you have
recently eaten, exercised, taken medication, or experienced stress*
. In
2
addition, if you have eaten recently, the blood glucose level from a finger
prick can be up to 70 mg/dL higher than blood drawn from a vein (venous
sample) used for a lab test*
. Therefore, it is best to fast for eight hours be-
3
fore 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.
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