Objective: To study the correlation of real-time continuous monitoring system (RT-CGMS) with venous glucose and capillary glucose values.
Methods: A total of 33 diabetics received RT-CGMS for 5 days. Fasting venous glucose values were measured at Days 1, 3 and 5 and capillary glucose values recorded 7 times daily. The methods of correlation coefficient, error grid analysis (EGA) and Bland-Altman analysis were employed to assessed the correlation, accuracy and agreement of RT-CGMS with venous glucose and capillary glucose values respectively. The mean amplitude of glucose excursions (MAGE) was calculated during RT-CGMS testing periods.
Results: (1) The correlation coefficient of RT-CGMS with vein glucose and capillary glucose values were 0.936, 0.933 (P < 0.01); (2) The analysis results of EGA showed that 98.67%, 98.64% of venous and capillary values fell in the A and B zones and 1.33%, 1.36% fell in the D zone; (3) The agreement analysis showed that RT-CGMS readings were in close agreement with venous glucose and capillary glucose results; (4) The patients at the same MAGE levels had obvious differences in HbA1C.
Conclusion: There is a high level of correlation, accuracy and agreement between RT-CGMS and venous glucose and capillary glucose values.