What affects your blood glucose meter’s accuracy and how to test it

Checking your blood glucose meter for accuracy is an important step towards getting the right readings.

Each person living with diabetes needs individualised diabetes care. Some people living with diabetes do not need blood glucose monitoring, but most do. Importantly, it provides you and your health care team with more information about the effect of your diet, activity level and medications on your blood glucose.

There are a range of blood glucose monitors available. Your diabetes health care professionals can guide you to the meter(s) that will best suit your needs. You should receive training to use your meter correctly.

Blood glucose monitor accuracy & performance

Blood glucose monitors are considered accurate if the result is within 15 percent of a laboratory result.

They are usually reliable but it is also important to know the factors that can affect the meter’s accuracy. Table 1 outlines important things to consider to ensure your blood glucose monitor performs well.

Table 1

Factors affecting the accuracy of a meter Solution
Blood Glucose Monitor Store the meter at room temperature. Replace batteries as needed.
Test Strips Each meter has specific strips, which must be in date, stored in their container or their individual wrapping.

Store at room temperature, avoid high heat, moisture or humidity.

Some meters must be coded to each container of test strips, so ensure the codes match if this is required.

The test strip must be fully inserted into the blood glucose monitor.

Hands or testing site Wash and dry hands thoroughly. If you choose an alternate site from the fingertip it may not be as accurate when blood glucose levels are rising or falling rapidly.
Blood Ensure enough blood is added to the test strip.

If you are dehydrated or have anaemia (low red blood cell count) your results may be less accurate.

Manufacturers have quality control solutions for each meter to allow a check of the accuracy of blood glucose meters.

Generally, it is recommended to use these liquid quality control solutions every time you open a new container of test strips, if you drop your blood glucose meter or whenever you get an unusual blood glucose result.

The quality control checks are easy to perform. You follow the same procedure as a blood glucose check but instead of adding blood to the test strip, you use the liquid control solution. The result should match the values given on the control solution label.

Expiration date for control fluid

Control solutions are available online or you can order them through your pharmacy.

The expiration date for the control solutions is three months after opening, or if unopened, until the expiration date on the box is reached.

Some pharmacies stock control solutions for some meters and depending on their demands they may check your meter for you.

Check with your CDE

However, you can always ask your credentialled diabetes educator (CDE) to do the quality control check for you at your appointment. Importantly, let your educator know when you book your appointment which meter you have so they can have the correct control solutions on hand.

Lastly, if you have concerns about your meter, discuss it with your CDE or contact the manufacturer.

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