How Accurate is Your Blood Glucose Monitor?

Published on
By : Suvarna Sheth

Blood glucose monitors that are marketed and sold to consumers may not be as accurate as regulatory bodies, or consumers would hope,  according to a recent study.

The study assessed the accuracy of 18 blood glucose monitors (BGM) cleared by the U.S. FDA, representing a large majority of products that are currently available today.

What was the Study Design?

A total of 1,035 people with Type 1, Type 2 or prediabetes were selected to have blood glucose levels tested on six different systems. The average age of participants was 51 years old, and 54% were women.

A reference plasma sample was also prepared for plasma testing at a lab. The BGMs came from retail places and tested in three studies. In each study, BGM was tested on 115 subjects.

A compliant blood glucose reading was defined as being 15% of the reference plasma value for blood glucose at least 100 mg/dL or within 15 mg/dL for blood glucose of less than 100 mg/dL.

The compliant readings in each study were then compared against standards. The researchers also took into consideration other factors of accuracy in their analysis.

What were the results?

The researchers found that six of the 18 systems met the predetermined accuracy standard in all three studies. Those BGMs included Counter Next (Bayer), Accu-Chek Aviva Plus (Roche), Walmart Reli-On Confirm Micro (Arkray), CVS Advanced (AgaMatrix), FreeStyle Lite (Abbott Diabetes Care) and Accu-Check SmartView (Roche).

They found that five monitors met the accuracy standard in two studies, three met it in one study and four did not meet the accuracy standard in any of the three studies.

The six top-performing blood glucose monitors based on the accuracy standard also met the four additional standards, whereas the 12 lower-ranking blood glucose monitors showed a wide array of overall performance with an overall compliant proportion ranging from 71% to 92%.

The researchers conclude that FDA cleared BGMs do not always meet the level of analytical accuracy currently required for regulatory clearance. “This information could assist patients, professionals, and payers in choosing products and regulators in evaluating post-clearance performance,” they state in their conclusion.

The study authors received a grant from Abbott Diabetes Care. Klonoff is a consultant for Ascensia, AstraZeneca, EOFlow, Intarcia, Lifecare, Novo Nordisk, and Voluntis. Please reference the study for a full list of financial disclosures.


  1. “FDA approved blood glucose monitors not always accurate.” October 9, 2018. Healio. Retrieved:
  2. “Investigation of the Accuracy of 18 Marketed Blood Glucose Monitors.”