. Author manuscript; available in PMC: 2008 Feb 22.

Published in final edited form as: Diabetes Technol Ther. 2003;5(5):781–789. doi: 10.1089/152091503322526987

Table 4.

Comparison of Accuracy of Original and Modified Sensors

	Original Sensors N=5,658 Paired Values	Modified Sensors N=1,120 Paired Values	P-value
Relative Absolute Difference Median (25^th, 75^th percentiles)	19% (9%, 36%)	11% (5%, 23%)	< 0.001
Modified Clarke Error Grid Zone A percentage	58%	78%	< 0.001
Modified Clarke Error Grid Zone A+B percentage	93%	98%	<0.001
ISO Criteria Met According to Reference Glucose Level^*
≤70 mg/dL	41%	48%	0.37
71–120 mg/dL	45%	60%	0.07
121–180 mg/dL	53%	70%	0.02
181–240 mg/dL	60%	77%	0.004
>240 mg/dL	58%	81%	0.007
All Values	53%	72%	< 0.001
Variation of Accuracy Among Sensors^†	N=112 Sensors	N=25 Sensors
Sensors with Median RAD <10%	9%	36%	0.01
Sensors with Median RAD <20%	54%	88%	<0.001
Sensors with Median RAD <30%	80%	100%	<0.001
Sensors with ≥80% of Values Meeting ISO Criteria	9%	24%	0.07
Sensors with ≥60% of Values Meeting ISO Criteria	35%	80%	< 0.001

ISO criteria: for reference glucose value ≤75 mg/dL, CGMS value ±15 mg/dL and for reference glucose value>75 mg/dL, CCGMS value within ±20%.

^†

Excludes 3 original sensors with fewer than ten paired reference glucose values.