A Comparative Effectiveness Analysis of Three Continuous Glucose Monitors The Navigator, G4 Platinum, and Enlite [*=left]Edward R. Damiano, PhD1 [*=left]Katherine McKeon, MEng1 [*=left]Firas H. El-Khatib, PhD1 [*=left]Hui Zheng, PhD2 [*=left]David M. Nathan, MD3 [*=left]Steven J. Russell, MD, PhD3 [SUP]1[/SUP]Department of Biomedical Engineering, Boston University, Boston, MA, USA [SUP]2[/SUP]Biostatistics Center, Massachusetts General Hospital, Boston, MA, USA [SUP]3[/SUP]Diabetes Research Center, Massachusetts General Hospital, Boston, MA, USA Steven J. Russell, MD, PhD, Diabetes Research Center, Massachusetts General Hospital, 50 Staniford St, Ste 301, Boston, MA 02114, USA. Email:firstname.lastname@example.org Abstract The effectiveness and safety of continuous glucose monitors (CGMs) is dependent on their accuracy and reliability. The objective of this study was to compare 3 CGMs in adult and pediatric subjects with type 1 diabetes under closed-loop blood-glucose (BG) control. Twenty-four subjects (12 adults) with type 1 diabetes each participated in one 48-hour closed-loop BG control experiment. Venous plasma glucose (PG) measurements obtained every 15 minutes (4657 values) were paired in time with corresponding CGM glucose (CGMG) measurements obtained from 3 CGMs (FreeStyle Navigator, Abbott Diabetes Care; G4 Platinum, Dexcom; Enlite, Medtronic) worn simultaneously by each subject. The Navigator and G4 Platinum (G4) had the best overall accuracy, with an aggregate mean absolute relative difference (MARD) of all paired points of 12.3 ± 12.1% and 10.8 ± 9.9%, respectively. Both had lower MARDs of all paired points than Enlite (17.9 ± 15.8%, P < .005). Very large errors (MARD > 50%) were less common with the G4 (0.5%) than with the Enlite (4.3%, P = .0001) while the number of very large errors with the Navigator (1.4%) was intermediate between the G4 and Enlite (P = .1 and P = .06, respectively). The average MARD for experiments in adolescent subjects were lower than in adult subjects for the Navigator and G4, while there was no difference for Enlite. All 3 devices had similar reliability. A comprehensive head-to-head-to-head comparison of 3 CGMs revealed marked differences in both accuracy and precision. The Navigator and G4 were found to outperform the Enlite in these areas.