title: A Multicenter Performance Evaluation of a Blood Glucose Monitoring System in 21 Leading Hospitals in Spain.
abstract: BACKGROUND
  Self-monitoring of blood glucose is crucial for the effective self-management of diabetes. The present study evaluated the accuracy of the Contour® XT blood glucose monitoring system (BGMS) compared to the reference method in a large multicenter study under routine lab conditions at each hospital site.
  
  
  METHODS
  This study was conducted at 21 leading hospitals in Spain using leftover whole blood samples (n = 2100). Samples were tested with the BGMS using 1 commercial strip lot and the local laboratory hexokinase method. BGMS accuracy was assessed and results were compared to ISO 15197:2013 accuracy limit criteria and by using mean absolute relative difference analysis (MARD), consensus (Parkes) error grid (CEG), and surveillance error grid analyses (SEG).
  
  
  RESULTS
  Pooled analysis of 2100 measurements from all sites showed that 99.43% of the BGMS results were within the ranges accepted by the accuracy limit criteria. The overall MARD was 3.85%. MARD was 4.47% for glucose concentrations < 70 mg/dL and 3.81% for concentrations of 70-300 mg/dL. In CEG, most results (99.8%) were within zone A ("no effect on clinical action"); the remaining ones (0.2%) were in zone B ("little to no effect on clinical action"). The SEG analysis showed that most of the results (98.4%) were in the "no risk" zone, with the remaining results in the "slight, lower" risk zone.
  
  
  CONCLUSIONS
  This is the largest multicenter study of Contour XT BGMS to date, and shows that this BGMS meets the ISO 15197:2013 accuracy limit criteria under local routine conditions in 21 leading Spanish hospitals.
authors.affiliation: Core Lab, Hospital Clinic, Barcelona, Spain jlbedini@clinic.ub.es.
authors.forename: José Luis
authors.initials: JL
authors.lastname: Bedini
authors.affiliation: Bayer HealthCare LLC, Medical Care, Mishawaka, IN, USA.
authors.forename: Jane F
authors.initials: JF
authors.lastname: Wallace
authors.affiliation: Bayer HealthCare Germany, Leverkusen, Germany.
authors.forename: Thorsten
authors.initials: T
authors.lastname: Petruschke
authors.affiliation: Bayer HealthCare LLC, Medical Care, Whippany, NJ, USA.
authors.forename: Scott
authors.initials: S
authors.lastname: Pardo
mesh_terms: D001786:Blood Glucose / Q000032:analysis*; D015190:Blood Glucose Self-Monitoring / Q000379:methods* / Q000592:standards*; D006801:Humans; D013030:Spain
chemical_list: D001786:Blood Glucose
keywords: Contour XT; accuracy; blood glucose monitoring system; consensus (Parkes) error grid; diabetes mellitus; surveillance error grid