Why do sugar readings differ with finger prick and venous blood methods?

Q: There is a huge difference in my blood sugar level when I compare the results of finger prick method and venous glucose method, is this common? The difference with the venous glucose test done in the traditional way and the gadget is of around 40 mg/dl. It often misleads. Please advise.

A:A difference of 7-10% is acceptable between these two methods. Few precautions areimportant before comparison:1. Both the readings from same sample or same time, even a gap of 10 minutes will show a significant difference.2. Once the bottle of strips is opened these should be used with in three months time irrespective of the expiry date on the strip bottle.3. Standardise your meter frequently, if problem contact the person from whom you purchased the meter.