COMPARING METER AND LABRATORY 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 information on Limitations.)
To make an accurate comparison between meter and laboratory results, follow the guide-lines below.
Before you go to the lab:
While at the lab:
- Perform a control solution test to make sure that the meter is working properly.
- It is best to fast for at least eight hours before doing comparison tests.
- Take your meter with you to 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,
especially if you have recently eaten, exercised, taken medication, or experienced stress*4
In addition, if you have eaten recently, the blood glucose level from a finger stick can be up to 3.9 mmol/L higher
than blood drawn from a vein (venous sample) used for a lab test*5
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.
*4: Surwit, R.S., and Feinglos, M.N.: Diabetes Forecast (1988), April, 49-51.
*5: Sacks, D.B.: “Carbohydrates. “ Burtis, C.A., and Ashwood, E.R.( ed.),
Tietz Textbook of Clinical Chemistry. Philadelphia: W.B. Saunders Company (1994), 959.