SUN-540 - Comparison of the Sibionics® Continuous Glucose Monitoring System with Capillary Glucose Measurements in Children with Type 1 Diabetes under Real-Life Conditions: A Prospective Observational Study

Objective: To evaluate analytical agreement and clinical concordance between the Sibionics® continuous glucose monitoring system (CGMS) and capillary blood glucose (CBG; Contour Plus Elite®) measurements in children with type 1 diabetes (T1D). Secondary objectives included assessment of device performance during hypo- and hyperglycemia, temporal changes in accuracy over sensor wear, and patient-reported experience.

Methods: This prospective observational cohort study enrolled children with T1D aged 6–18 years who used the Sibionics® CGMS for 14 consecutive days. Participants performed CBG measurements at eight standardized daily time points, with additional measurements during hypoglycemia ( < 70 mg/dL) and hyperglycemia (>180 mg/dL). Paired CGMS–CBG values were matched using synchronized timestamps. Accuracy and agreement were evaluated using mean absolute relative difference (MARD), median absolute relative difference (ARD), Bland–Altman analysis, 20/20 accuracy criteria, and Clarke Error Grid (CEG) analysis. User satisfaction and device experience were assessed using a Likert-scale questionnaire.

Results: A total of 66 participants (57.6% female; mean age 13.4 ± 2.7 years) contributed 5,573 paired measurements. The overall MARD was 13.4 ± 9.5%, with a median ARD of 12.1% (interquartile range [IQR], 6.0–18.9). Clarke Error Grid analysis demonstrated that 94.9% of paired values fell within clinically acceptable zones A and B, with no measurements in zones D or E. According to 20/20 accuracy criteria, 80.5% of paired measurements met target performance thresholds.
MARD was higher during nighttime measurements (16.2 ± 9.3%) and hypoglycemia (17.8 ± 11.7%), whereas lower values were observed during hyperglycemia (11.0 ± 7.9%). Accuracy improved with increasing time-in-range (TIR); participants with TIR >70% exhibited a lower MARD (11.9 ± 9.3%). Longitudinal analysis demonstrated reduced agreement on day 1, peak accuracy on days 4–6, and a gradual decline by day 14. Bland–Altman analysis revealed a mean CGMS bias of −17.3 mg/dL relative to CBG.
Patient-reported satisfaction was high (ease of use, 4.6/5; willingness to reuse, 4.4/5; discomfort, 1.4/5), and 70% of participants reported making treatment or lifestyle modifications based on CGMS data.

Conclusion: Under real-world conditions, the Sibionics® CGMS demonstrated good overall agreement with capillary glucose measurements in pediatric patients with T1D. Accuracy was reduced during hypoglycemia and nighttime periods. High usability and patient satisfaction support the clinical utility of this system in pediatric diabetes management.

Keywords: Type 1 diabetes; continuous glucose monitoring system; Sibionics®; capillary blood glucose; Contour Plus Elite®; real-world data