When you weigh yourself, you are reasonably sure the result is accurate. So why is measuring blood sugar accurately not as simple as stepping on a scale? This is because our glucose level is affected by other factors such as the multiple components that make up your blood. Blood glucose meter technology has improved to lessen the impact of the other factors, but even the newest state-of-the-art meters have an FDA acceptable tolerance of +/- 20%. All meter manufacturers receive questions about accuracy, but newer meters may provide the most accurate results.
New Standards for meters after 2016
Because older meters were notorious for poor accuracy, the FDA implemented an accuracy study guideline in 2016 that all new meters must pass before approval. The tighter tolerance implemented is +/-20% for 99% of the readings. Pops Rebel has been through this study successfully and submitted data to the FDA that met an even tighter standard!
What does it mean for a meter to have 99% of results with the new standard of +/-20% accuracy?
Let’s assume that we magically know your true glucose is 100 mg/dl. If you check your blood sugar 100 times, an accurate meter may show 99 results within the range of 80 to 120 mg/dl, with most of the results nearer your true glucose level. And it is still acceptable that one result may be even further out of the +/-20% tolerance.
This table will help you understand the +/- 20% range for various glucose levels.
Can I compare meters?
As people with diabetes, we often want to compare a new meter with our old one. We often come to believe that the meter we have been using is accurate. But is it? Have you ever stepped on a scale at the doctor’s office and it read differently than your home scale? Which one is accurate? We usually want to believe the one we are most used to, or the one that gives us the lower reading.
Understanding this difference becomes even more challenging when you compare glucose meters. The two meters may use different technology, one or both of them may not have passed the FDA’s accuracy testing, and they both allow a tolerance of results. Let’s assume your glucose is 220 mg/dl. Using our table above, it is possible that two state-of-the are meters may show results of 176 and 264 and both be correct! As this graph shows, the higher the actual glucose, the window of allowed results gets larger.
Newer meters, like Pops Rebel, may implement new technology to give an even truer glucose result, and comparing old to new can be very challenging.
Comparing becomes even more difficult when a Continuous Glucose Monitor is involved as we discuss in our BGM vs CGM blog. Another challenge we have written about is comparing your meter readings to your A1c results.
What can I do?
There are some basic things you can do that will help you understand and control differences between meter results.
- Wash and dry your hands before you test. One study showed blood sugar results went from 80 mg/dl to 275 mg/dl just by handling a peeled apple!
- Keep your testing supplies in generally room temperature storage to keep them the most accurate.
- Note that your blood sugar may be changing rapidly after you eat, after you exercise, and after you take your medications.
- Stay well hydrated!