zaro

What is the 80/20 rule for Dexcom?

Published in Dexcom Accuracy 2 mins read

The "80/20 rule" for Dexcom, specifically concerning the Dexcom G6 Continuous Glucose Monitoring (CGM) system, refers to the expected accuracy standards that define how closely the sensor's glucose readings should align with a traditional blood glucose meter (BGM) reading. This rule outlines the acceptable deviation based on whether the blood glucose level is above or below a specific threshold.

The Dexcom G6 Accuracy Standard

The core of the 80/20 rule for Dexcom centers on two distinct accuracy criteria, depending on the blood glucose value measured by a meter. This standard ensures that Dexcom G6 readings provide reliable information for managing diabetes.

Here's a breakdown of the accuracy expectations:

Blood Glucose Meter Value Dexcom G6 Reading Must Be Within
80 mg/dL or higher 20% of the meter value
Under 80 mg/dL 20 mg/dL of the meter value

This means the accuracy requirement shifts based on whether the blood sugar is at or above 80 mg/dL or below it.

Practical Examples of the 80/20 Rule

To better understand how this rule applies, consider these examples:

  • When your blood glucose is 80 mg/dL or higher:

    • If a blood glucose meter reads 100 mg/dL, the Dexcom G6 reading should be within 20% of 100 mg/dL. This means the Dexcom reading should fall between 80 mg/dL (100 - 20%) and 120 mg/dL (100 + 20%) to be considered accurate according to this rule.
    • If a blood glucose meter reads 200 mg/dL, the Dexcom G6 reading should be within 20% of 200 mg/dL. This means the Dexcom reading should be between 160 mg/dL (200 - 20%) and 240 mg/dL (200 + 20%).
  • When your blood glucose is under 80 mg/dL:

    • If a blood glucose meter reads 70 mg/dL, the Dexcom G6 reading should be within 20 mg/dL of 70 mg/dL. This means the Dexcom reading should be between 50 mg/dL (70 - 20) and 90 mg/dL (70 + 20).
    • If a blood glucose meter reads 50 mg/dL, the Dexcom G6 reading should be within 20 mg/dL of 50 mg/dL. This means the Dexcom reading should be between 30 mg/dL (50 - 20) and 70 mg/dL (50 + 20).

Why Dexcom Accuracy is Important

Adhering to these strict accuracy standards is crucial for a Continuous Glucose Monitoring system. Accurate readings allow individuals with diabetes to make informed decisions about insulin dosing, meal planning, physical activity, and overall diabetes management, contributing to better health outcomes and peace of mind.