Accuracy of the SEVEN® Continuous Glucose Monitoring System: Comparison with Frequently Sampled Venous Glucose Measurements

Abstract

Measurements of the DexCom SEVEN system were found to be consistent and accurate compared with venous measurements made using a laboratory reference method over 7 days of wear.

Performance Evaluation of Three Continuous Glucose Monitoring Systems: Comparison of Six Sensors Per Subject in Parallel

“…This result is in agreement with other studies incorporating EGA analysis. 3,8,9,12,13,[16][17][18][19]21,22 Only 70% to 80% of paired readings were found to be within the system accuracy limits of ISO 15197:2003. 20 According to ISO 15197, 95% of device readings must be within ±15 mg/dl or ±20% of the paired reference readings below or above 75 mg/dl.…”

“…13 The study presented here is, to the best knowledge of the authors, the first to use two sensors of three different CGM systems in parallel for the respective entire lifetime of the sensor, thus allowing the evaluation of accuracy (with regard to BG measurements) as well as sensor-to-sensor precision between different sensors of one type of CGM system. 23 In other studies in which more than one sensor was used per subject, only one type of CGM system was used, 3,4,6,[8][9][10][11]15 and in studies that compared multiple CGM systems, only one sensor per subject was used. 2,7,12,19 In this study, both aspects were combined, thus allowing an evaluation in which groups of six sensors (i.e., two sensors of each of three CGM systems in one individual subject) follow identical glycemic excursions.…”

“…Precision absolute relative difference was calculated in a similar fashion, but instead of sensor-to-BG differences, sensor-to-sensor differences were calculated, with the mean of the interpolated and the noninterpolated CGM readings replacing the capillary BG readings. 8,9 In addition to these parameters, difference plots are provided to show the difference between single CGM readings and paired capillary BG readings. These plots also show the system accuracy limits of ISO 15197:2003, 20 an international standard for system accuracy evaluation of systems for self-monitoring of blood glucose (SMBG).…”

“…In 2008, the Clinical and Laboratory Standards Institute published POCT05-A, which provides recommendations for study design and parameters of interest in the performance evaluation of CGM systems. 1 Multiple studies investigating CGM systems were published over the years; [2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19] only one claimed to use procedures recommended in POCT05-A. 13 A comparison of these studies, however, is difficult due to variations in subject groups 11 and study design, including use of different devices for calibration of CGM systems and for reference measurements, either overall or for different study phases.…”

“…13 A comparison of these studies, however, is difficult due to variations in subject groups 11 and study design, including use of different devices for calibration of CGM systems and for reference measurements, either overall or for different study phases. [2][3][4][6][7][8][9][10]12,13,16,17 Given that comparability of different CGM systems is heavily influenced by these factors, it is thus improved when the different CGM systems are worn simultaneously by the same subjects under identical conditions (e.g., in head-to-head comparisons). There are studies in which different CGM systems were compared under such conditions, 2,7,12 but in these cases, only one sensor per CGM system was worn by the subjects.…”