Accurate Blood Sugar Readings
Making sure your meter readings are right
Here are a few simple steps to check the accuracy of your diabetic testing meter and provide peace of mind, should you think you may be getting inaccurate readings
Check These Things First
The first thing to do when you get a reading that seems that it might not be accurate is to do a control solution test on the very next strip in the bottle. If the test shows the strips are not accurate, call the manufacturer of your meter and get them to send another box of strips. Also, you might want to make sure that your meter's batteries are still good.
The usual life of a meter is between three and five years. If your meter is over five years, the meter readings may not always be accurate. If your meter is over five years old, you may want to begin thinking about replacing it.
Often people think their meter is giving them false readings, after comparing their meter with someone else's or with the readings they get from their doctor's office or lab. Once they see a discrepancy between meters, they often begin to doubt the accuracy of their own meter and they want to immediately get a new one.
Comparing One Meter Reading With Another
Strange as it may first seem, it is totally possible for one meter to be off as much as thirty points from another meter and for both readings to be accurate. How can this be?
Why Readings Can Be Different
If you have measured your meter readings against a doctor's lab there may be a difference because doctor's labs remove the red blood cells and test the blood plasma only, while your meter may be testing the whole blood. The reason is that a meter that reads whole blood can be twelve per cent lower than a meter that reads blood plasma. This does not mean that one is more accurate than the other any more than a measurement in kilometers is more accurate than a measurement in miles. Just different.
Twelve per cent does not seem like much, but there is one other factor that must be considered. Manufacturers of meters consider their meters accurate if their meter's readings fall within a plus or minus 20 points of another meter.
So, if you test your blood and get a reading of 120 and then test yourself with a friend's meter, you could get a reading of anywhere between 112 and 152 and both readings could be accurate. This accounts for the plus or minus 20 point discrepancy added to twelve percent increase from a plasma meter versus a whole blood meter.
One other factor to consider is that you take your blood from your finger. Doctor's offices, especially doctor's labs will often draw blood from your vein. There will automatically be a discrepancy because blood taken from the veins will register a different reading from blood taken from a capillary.
There is also one other point to consider. Let's say you take your reading at home before your doctor's appointment. Then you get in your car and drive through traffic to your doctor's office and the doctor takes your reading over a half an hour after you tested at home. When you look at your reading at your doctor's office, it is quite different than the one you just took at home. But bear in mind that driving in traffic causes stress which elevates your blood sugar level. Also every time your heart beats, your blood sugar level changes slightly. Readings over a half hour apart can vary a fair amount.
So. before you throw away your meter, or let your doctor give you a new meter you may really not want, because your reading and the reading from your friend's or doctor's meter don't match, wait a day and test your blood with your own meter and see if the readings you get are normal for you. If after a day the readings seem wrong, then you may want to get a new meter. If the readings seem to be what you expect, then keep your meter and feel more at ease knowing that blood sugar testing is not an exact science and there can be discrepancies between meters.
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