How do I know if my meter is giving me accurate results?
Majority of Virta’s patients enter the program already owning a blood glucose testing device, and you may find yourself comparing results from your Keto-Mojo meter with your personal device. Different meter brands have different technologies, and tend to vary in measurements and this variance should not be considered inaccuracy by Keto-Mojo. Please see below for detailed accuracy information for both glucose and ketone readings.
If I have the GK+ meter, can I use the control solution to test for accuracy?
Yes! The control solution that comes with your GK+ meter is intended to be used when you believe your meter is giving inaccurate results. Please visit our detailed article titled, "How and When to use Control Solution with your Keto-Mojo GK+ Meter".
Important Changes about GK+ Meter from older Keto-Mojo Model
The new GK+ meter is more sensitive than the older model meters. This also makes them more accurate - in fact, the new GK+ meter tested within 10% accuracy for glucose 96% of the time in its test trials of 100s of tests for FDA regulation. The GK+ meter has eight sensor connectors for measuring the blood, whereas the earlier meter models only had four. This makes the meter ultra-sensitive to interstitial fluid and microscopic debris. The earlier generation models were very accurate, within 10% accuracy 75% of the time, but not as accurate as the new GK+ model. The older model meters are also more forgiving to imperfect testing practices, such as not wiping away the first droplet or squeezing near the stick hole.
Following all testing procedures is necessary with the new meter due to the sensitivity to interstitial fluid and microscopic contaminants on the hands. The first droplet will often read higher if you do not have clean hands, wipe away the first droplet, and make sure the strip is pressed firmly into the strip portal so all 8 sensors connect.
Troubleshooting for Varying or High Results
- Do you use alcohol to clean the finger or make sure your finger is washed with unscented soap, rinsed well with all soap residue rinsed away and completely dry?
- Are you always wiping away the first drop of blood (with tissue) and test on the 2nd and/or 3rd drop?
- Do you NOT squeeze near the prick hole to get enough blood? Squeezing near the prick hole will force out interstitial fluid that skews results. (Here is a video on how to squeeze for good blood flow properly).
Comparing Back-to-Back Results
Intuitively, it may seem that comparing back-to-back results from the same glucose or glucose-ketone meter would be a helpful way to determine its accuracy or to receive more accurate readings, but that’s actually not the case.
First, as discussed below in the Accuracy sections of this article, keep in mind that expected variations in readings will occur:
- +/- 15% variation compared to baseline lab results, 95% of the time
- +/- 20% variation compared to baseline lab results, 99% of the time
Therefore, for example, a repeat reading of a lab-validated glucose sample that’s 100 mg/dL would be expected to range from 85-115 mg/dL with a home glucometer.
Beyond that, performing back-to-back readings at home further decreases accuracy for these reasons:
- If you use a single sample (blood droplet), prolonged exposure to air skews readings because glucose oxidizes (reacts to oxygen).
- Blood glucose levels can change rapidly in your body, so even samples taken close to one another in time can be different.
- Taking readings using samples from different fingers may result in differences because the glucose content of fluids from different body areas can be different.
GK+ Glucose Accuracy
When testing your blood glucose, you may receive different measurements even from the same blood sample. This is not uncommon in home-testing given the small size of your sample. Keto-Mojo meters exceed all FDA standards. For home glucose meters, the following accuracy standards are set by the FDA, and are as follows:
- 95% of all measured blood glucose meter values must be within +/-15% across the measuring range; and
- 99% of meter values must be within +/-20% across the measuring range.
The Keto Mojo meter exceeds current FDA standards for point of care testing. For readings equal or over 75 mg/dL, measurements have an accuracy of:
- 100% within 20%
- 100% accuracy within 15%
- 96% accuracy within 10%
- 62% accuracy within 5%
This means that 100% of the time, your readings will be within 20% of your exact measurement.
For example, a glucose meter result of 100 mg/dL could vary on the downside to 80 mg/dL or on the upside to 120 mg/dL and still be considered accurate.
For readings under 75 mg/dL, measurements are accurate within a range of:
- 100% within 15 mg/dL
- 97% within 10 mg/dL
- 67% accuracy within 5 mg/dL
Ketone Accuracy
Alike glucose, ketone levels may vary for the reasons discussed above. If you feel you are getting inaccurate ketone readings, you should always perform a control solution test to see if your meter and strips are testing within range. Please visit our detailed article titled, "How and When to use Control Solution with your Keto-Mojo GK+ Meter".
Why am I getting the same ketone readings multiple days in a row?
Ketone levels are slower to change than glucose. It is not uncommon to receive the same ketone reading over multiple days, especially if you are testing at the exact same time every day. We suggest giving yourself a 5 day window to make changes to see if those changes are reflected in your ketone readings, and also try testing at different times of the day over those 5 days. If you go more than 5 days without seeing any difference in your ketone readings, you should perform a control solution test to make sure the strips and meter are working correctly!
What can interfere with my glucose or ketone measurements?
Here are some of the most common factors that can affect your blood glucose and ketone measurements.
- Strip placement in the meter port and blood fill level. Make sure your strip is firmly placed into the port, and that the blood sample completely fills the channel.
- Hydration! If you are dehydrated or anemic, your results may be less accurate.
- Hygiene and testing protocol. Use the provided alcohol swabs before every test (or wash your hands) and make sure to code sync each new vial of ketone strips.
- Altitude, temperature, humidity.
- Interfering substances. Some substances, such as Tylenol, elevated uric acid, or low glutathione may interfere with your glucose test results.
- Food or contaminants like lotions, exogenous ketones, and MCT oil on the skin or strips (i.e. if strips come into contact with a surface that has a contaminant).
- Exposure to air. Studies have shown that extended exposure of the blood sample to air can result in readings with a 10% variance, as a result of evaporation, coagulation, and changes in a small volume of blood.
- Strip expiration. Use your strips within 6 months of opening the vial.
I still think my meter is inaccurate, what do I do next?
Please visit our support center articles to review best practices for taking measurements:
If these troubleshooting tips have not solved your issue, please contact our support team, here.
Thank you,
Virta Support