Continuous glucose monitoring (CGM) may help to improve diabetes therapy. An international consensus paper calls for standards in the CGM data analysis, suggesting reports of standardized “key metrics.” Data from people without diabetes might be useful in the interpretation of the suggested key metrics.

In this study, 39 adults without diabetes used two iscCGM systems (FreeStyle Libre) in parallel for the 14-day sensor life. Based on collected iscCGM data the key metrics mean glucose, standard deviation, glycemic variability (CV), time in various glucose ranges, low blood glucose index (LBGI) and high blood glucose index (HBGI) were calculated. Instead of estimated A1C, its recently proposed replacement, the glucose management index (GMI), was calculated.

Out of 78 sensors, 73 sensors achieved a data capture rate of at least 80%, the minimum required by the consensus statement. Direct comparison of the two sensors worn in parallel was possible for 35 subjects. Specific results are provided in the Table.

In this study, some key metrics calculated from iscCGM data of adults without diabetes showed considerable variation between subjects as well as within subjects. Although the reliability of these key metrics depends on how accurately CGM data depict “true” glucose levels, these findings may be helpful in the interpretation of these key metrics in diabetes patients.


G. Freckmann: Advisory Panel; Self; Abbott, Novo Nordisk Pharma GmbH, Sensile Medical AG. Consultant; Self; Metronom Health Europe, Roche Diabetes Care, Sanofi. Speaker's Bureau; Self; Ascensia Diabetes Care, Dexcom, Inc., Ypsomed AG. S. Pleus: None. S. Ulbrich: None. D. Waldenmaier: None. A. Baumstark: None. M. Link: None. C. Haug: None.

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