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Calibration Algorithms and Factory-Calibration

Modern CGMs use sophisticated calibration algorithms, with many now featuring factory-calibration that eliminates the need for user fingerstick calibrations.

Calibration Algorithms and Factory-Calibration

The Role of Calibration

CGMs rely on calibration algorithms to translate raw sensor signals into accurate glucose readings.

Types of Calibration

User Calibration

Traditional approach requiring periodic fingerstick blood glucose measurements to adjust sensor readings.

Factory Calibration

Modern approach where sensors come pre-calibrated from manufacturing:

  • Abbott's FreeStyle Libre pioneered this approach
  • Dexcom G6/G7 use factory calibration
  • No user calibration required

How Factory Calibration Works

Manufacturers test each sensor batch against reference standards and program calibration parameters into the sensor or transmitter.

Pros and Cons

Factory Calibration Advantages

  • Convenience—no fingersticks needed
  • Reduced user error
  • Consistent performance from day one

Potential Drawbacks

  • May lack the precision of individualized calibration
  • Cannot account for individual physiological variations
  • Some users prefer the control of manual calibration