The Accuracy of a Blood Glucose Meter vs. a Lab Test and Why It Matters

Checking blood glucose levels is crucial to the management of diabetes, and accuracy is key. Insulin dose administration, diet plans, and minimizing health risks all rely on accurate readings. While there are different ways to check the amount of glucose in your blood, the most common are blood glucose meter (BGM) tests and lab tests. But how should we look at a blood glucose meter vs. a lab test? Are they both accurate? How do they fit into treatment? Finding the answers can help you confidently move forward with your diabetes management plan.

What Are BGM Tests?

A BGM test measures how much glucose is in your blood. A standard BGM test kit will come with a lancet to prick your skin (usually on your finger), test strips, and a logbook to track your levels. To perform a test, you insert a test strip into the meter and place a blood sample on the strip. But with the POGO Automatic^® Monitor, the test strips and lancet are integrated in a 10-test cartridge that you simply pop into the device, which means testing can take place in one simple step. The meter will analyze the sample and display the result on an easy-to-read screen. Your results are saved in the device and can be uploaded to an app.

FDA-cleared meters are often used in hospitals and doctors’ offices, and they’re also an efficient and safe way for people with diabetes to check their levels on their own. Regular testing at home lets you and your healthcare provider monitor trends, refine your treatment plan, and better manage your diabetes. This can be critical to reducing the risk of certain health conditions, including heart disease, stroke, and high blood pressure.

What Are Lab Tests?

Several lab tests are used to measure blood glucose, including random blood glucose, fasting blood glucose, and hemoglobin A1c tests. To perform these tests, a technician will take a blood sample from a vein (typically in the forearm) and submit the sample to a lab for testing. Results may take a few hours or days to come back.

Lab tests are essential for diabetes diagnosis. Once you’ve been diagnosed, your healthcare provider may order further lab testing if your BGM test readings are abnormal, if you are experiencing new symptoms, to assess your treatment plan, or when changing your treatment plan.

What Affects the Accuracy of a Blood Glucose Meter vs. Lab Test?

Many people living with diabetes find that their BGM test results differ from their lab results. This difference can be alarming and leave you wondering if you can trust your BGM to be accurate. But by taking a closer look at a blood glucose meter vs. a lab test and how they differ, you can understand why this can happen and what it means.

BGM and lab tests both evaluate blood glucose, but they do so in different ways.

Lab Glucose Tests

Lab glucose tests are similar to a BGM test in that they measure blood glucose in the moment and can detect short-term changes. But the results may differ from your BGM readings for a variety of reasons, including the following:

• The timing of sample collection vs. testing.
• Different equipment.
• Different methodology (plasma vs. whole blood).

Despite these variables, your BGM results usually correspond to lab test results.

A1c Tests

Unlike a BGM test, which reflects your blood sugar in the moment and can show sudden, short-term changes, an A1c test reflects your average blood sugar over the last two to three months (the life span of red blood cells). This long-term measurement is an excellent way to monitor how well your diabetes management plan is working, but it is looking at different parameters than your BGM and it is difficult to compare these two measurements.

Ensuring Accuracy

Consistently inaccurate BGM tests are a serious concern. These tests are important tools for day-to-day diabetes management and give your healthcare provider valuable information about your health. Without accurate results, you are left without the data you need to make informed decisions about your treatment.

When a BGM is described as accurate, that doesn’t mean it measures the exact amount of glucose in your blood each time you check. No device measures the glucose in your blood exactly; even a tiny drop of blood contains billions of glucose molecules. Much like when you take your temperature at home, repeated measurements might be slightly different from each other. Instead, accuracy is determined by how closely the BGM measurement corresponds with results from a “gold standard” instrument.

The FDA accuracy requirement is that 95% of all blood glucose values from the BGM are within 15% of the value measured by the lab instrument and that 99% of all blood glucose values from the BGM are within 20% of the value measured by the lab instrument. If the BGM does not satisfy the FDA requirements, it cannot be considered accurate.

If you are using an FDA-cleared device, you are one step closer to ensuring accuracy. But several factors can affect the accuracy of your BGM results, including test strip management, the testing site, and the cleanliness of the test site. Here are a few simple precautions to get the most accurate results:

• Always thoroughly wash your hands with soap and water before checking your levels.
• If you also choose to use alcohol to clean your finger, make sure you let it dry.
• Make sure your test strip is not damaged or expired and that it was properly stored before use.
• Use an appropriate blood sample size. Blood samples should be neither too large nor too small.
• Consider your test site. Blood taken from a finger might have a slightly different glucose concentration than blood taken from the forearm.
• Avoid excessive squeezing of the finger to get a blood sample.
• Make sure your testing supplies are within the temperature range specified by the manufacturer.
• Use only an FDA-cleared device.

If you have any concerns about the accuracy of your BGM, always consult your healthcare provider.

Manage Diabetes Confidently

When it comes to a blood glucose meter vs. lab test, both play vital roles in diabetes management. Following your healthcare provider’s recommended lab testing schedule and choosing a BGM that makes routine monitoring as easy as possible can ensure that you get the most out of testing.

POGO Automatic is an FDA-cleared automatic blood glucose monitor that simplifies the testing process and offers immediate results in one step. The POGO Automatic meets FDA accuracy requirements and automatically checks to ensure test strips aren’t expired before each test. In combination with a comprehensive diabetes management plan, using this innovative device is a powerful way to take charge of your diabetes and stay on track with your treatment.

Jaclyn Owens Jaclyn Owens is a product director specializing in diabetes management tools. She is committed to using technology to empower people with diabetes and help them take control of their health.

All content on this website is for educational purposes only and does not replace the guidance of your healthcare practitioner. Always seek the advice of your physician or other qualified healthcare provider with any questions you may have regarding a medical condition or treatment and before undertaking a new healthcare regimen, and never disregard professional medical advice or delay in seeking it because of something you have read on this website.