User's Manual

A1-38

 Comparing Monitor and Laboratory Results

The monitor provides you with whole blood equivalent 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 being 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*

. 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*

.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 meter 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.