Table 3.

Comparison of interstitial glucose measured by FSL-CGM and reference venous blood glucose based on standard analytical approaches

	Fasting (n = 17)	1 h post-OGTT (n = 17)	2 h post-OGTT (n = 17)	All (n = 51)
Time difference between paired samples ± SD (minutes)	8.8 ± 5.4	5.3 ± 5.0	7.9 ± 5.2	7.4 ± 5.3
Correlation coefficient (95% CI)	0.57 (0.12–0.83)	0.68 (0.30–0.88)	0.66 (0.26–0.87)	0.81 (0.69–0.89)
MAD overall (mmol/L)	−0.54	− 0.92	−0.89	− 0.78
MAD when ref. < 5.5 mmol/L (n = 21)				−0.58
MARD overall (%)	−12.2	−11.3	−13.2	−12.3
MARD when ref. > 5.5 mmol/L (n = 30)				−11.9
Within ISO 2013 criteria (%)	58.8	41.2	47.1	49.0

SD standard deviation; CI confidence interval; MAD mean absolute difference; MARD mean absolute relative difference; ISO international organization of standardization