title: FreeStyle Navigator Continuous Glucose Monitoring System with TRUstart algorithm, a 1-hour warm-up time.
abstract: BACKGROUND
  The first-generation FreeStyle Navigator® Continuous Glucose Monitoring System (FreeStyle Navigator CGM) requires a 10 h warm-up period to avoid inaccurate glucose readings caused by sensor insertion trauma and wound-healing processes. The performance of a second-generation FreeStyle Navigator CGM that begins reporting glucose 1 h after sensor insertion is described.
  
  
  METHODS
  Second-generation FreeStyle Navigator CGM performance was evaluated in an in-clinic study using the YSI Model 2300 STATPlus Glucose Analyzer as reference with 47 subjects with type 1 diabetes. The reference readings were taken at 15 min intervals, and the study was designed to emphasize the first 10 h of use.
  
  
  RESULTS
  The second-generation FreeStyle Navigator CGM exhibited continuous glucose error grid analysis ratings of 93.7% "clinically accurate," 3.6% "benign errors," and 2.8% "clinical errors" and a mean and median absolute relative difference of 14.5% and 10.7%, respectively. The second-generation algorithm detected signal instability in the first 10 h of use and suspended the reporting of 14.1% of first day continuous glucose readings. The clinical accuracy of the second-generation FreeStyle Navigator CGM was similar for the first 10 h versus subsequent hours, with 92.6% and 94.2% "clinically accurate" readings, respectively.
  
  
  CONCLUSIONS
  The warm-up period for the second-generation FreeStyle Navigator CGM was reduced from 10 to 1 h, with minimal interruption of glucose reporting and without sacrificing clinical performance.
authors.affiliation: Abbott Diabetes Care, Alameda, California, USA. geoffmcga@gmail.com
authors.forename: McGarraugh
authors.initials: M
authors.lastname: Geoffrey
authors.forename: Ronald
authors.initials: R
authors.lastname: Brazg
authors.forename: Weinstein
authors.initials: W
authors.lastname: Richard
mesh_terms: D000328:Adult; D000465:Algorithms; D001786:Blood Glucose / Q000032:analysis*; D015190:Blood Glucose Self-Monitoring / Q000295:instrumentation / Q000379:methods / Q000592:standards; D002138:Calibration; D056902:Clinical Alarms / Q000592:standards; D003922:Diabetes Mellitus, Type 1 / Q000097:blood* / Q000150:complications / Q000453:epidemiology / Q000628:therapy; D004867:Equipment Design; D006801:Humans; D007003:Hypoglycemia / Q000175:diagnosis / Q000453:epidemiology / Q000209:etiology; D008875:Middle Aged; D018670:Monitoring, Ambulatory / Q000295:instrumentation* / Q000379:methods / Q000592:standards; D012680:Sensitivity and Specificity; D013997:Time Factors
chemical_list: D001786:Blood Glucose