CGM—How Good Is Good Enough?

Abstract

Continuous glucose monitoring (CGM) systems are more informative than the traditional self-monitoring of capillary blood glucose (BG). Although advances in CGM technology have significantly improved the clinical utility of CGM devices compared with earlier versions, it is often difficult to assess the accuracy and precision of current devices due to differences in assessment protocols and reporting of results. Because CGM sensor accuracy can impact both the clinical utility and patient acceptance of CGM use, it is important to consider the performance characteristics seen in the current systems when assessing the clinical value of this technology. Moreover, standardization of the metrics used to assess CGM accuracy and precision are needed to help developers, clinicians, and patients make informed decisions regarding the CGM systems they are considering. In this chapter, we discuss the most commonly used methods for the assessment of CGM system performance, the accuracy and reliability of current CGM systems, and the remaining unsolved technological and physiological hurdles.