HbA1c & GMI Estimator

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Manual Formula: GMI (%) = 3.31 + (0.02392 x Average Glucose in mg/dL).

Average Glucose (mg/dL)

The Math & Assumptions

The Glucose Management Indicator (GMI) was developed by Bergenstal et al. (2018) to replace "estimated A1c". It is calculated as: 3.31 + (0.02392 * Avg Glucose).

Note: GMI requires at least 14 days of CGM data with >70% active time to be statistically valid.

Next step: Understand how to improve this metric by focusing on Time in Range.