
February 9, 2003
Blood Tests and Insulin Injections
Question from Overland Park, Kansas, USA:
A medical professional told someone I know that glucose meters are deliberately designed to read low, especially at low blood glucose levels, as a safety measure. I can’t believe that meter manufacturers would handicap themselves this way in the quest for FDA approval, but I found similar information. Is there any basis to this information?
Answer:
While a variety of things can cause meter readings to be inaccurate (old strips, low battery, user technique), the FDA has quite strict guidelines for testing any meter. You might try looking at Performance of Three Blood Glucose Meters, by Catherine C Rheney and Julienne K Kirk, to see the kind of research that is published about meters. This article demonstrates the use of the error grid analysis (page 2 of the article). Such analysis is common and allows scientists to determine how far in error a meter is performing.
BS
Additional comments from Jane Seley, diabetes nurse specialist:
I think what you mean is that the meter says “Low” instead of an actual number when the blood glucose level is very low. This is indeed a safety mechanism because each meter is capable of giving an accurate reading within a certain range which varies from meter to meter. If the blood sugar goes below (or above) that range, it will not give a numerical answer because the accuracy is questionable outside of its proven to be accurate range.
JS