Become a Self-Test Pro When You Have Diabetes

Here’s how to outsmart the little things that can affect your blood sugar reading.

Lori Murray
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Did you know something like outdated test strips, humidity, a too-small blood sample on a test strip or wet fingers can render your test results unreliable? It’s true! So to get the most accurate results, watch for little problems with…

Your meter. Dirt, extreme tempera­tures and incompatible test strips can “taint” the reading.

The fix
. Keep your meter (and other testing supplies) at room temperature, and make sure it’s clean—especially the strip guide and test window. Some meters must be coded to each container of test strips, so be sure the code number in the monitor matches the one on the test-strip container.

Your test strips.
They could be damaged (for example, by heat or humidity), outdated or the wrong size.

The fix.
Check the expiration date of all your testing supplies. Throw out strips that are torn, bent or otherwise damaged, and do not use test strips from a cracked or damaged container. Watch the size, too: Test strips may look alike, but they are not all the same. Even if an incorrect test strip fits in your meter, it could still give you wrong results.

Your technique
. Dirty or wet fingers could affect the blood sample. So can squeezing your finger too tightly when putting a blood drop on the test strip. And if the drop is too small, your reading could be off—even if the meter is designed to give an error message when this happens.

The fix
. Before pricking your finger, wash your hands with warm, soapy water and dry them well. Put your hand down to let gravity help boost blood flow to your fingertips (you can also massage your hand). Rather than squeeze, let the blood flow freely from your fingertip. And finally: Apply a generous drop of blood to a whole test strip (never bend, cut or alter the strip). Do not add more blood to the strip after you’ve applied the first drop.

April 2013