Abbott FreeStyle Navigator User Manual Download

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Performance Characteristics

Note:

Please

cons

ult your healthcare team on how to use the information in this section.

Performance of the FreeStyle Navigator® Continuous Glucose Monitoring System was evaluated in a controlled

clinical study. The study was conducted in 3 centers and included a total of 58 subjects with diabetes. Each

subject wore two FreeStyle Navigator Sensors over a 5-day period. The subjects wore one sensor on the back of

the upper arm and one on their abdomen. The FreeStyle Navigator system was calibrated with capillary finger-

stick measurements using the built-in FreeStyle Blood Glucose Meter at approximately 10, 12, 24 and 72 hours

after insertion of the sensor.All measurements were performed by a trained clinic study staff or the subject.
During the study, subjects came to the clinical center for frequent glucose samples measured once every

15 minutes on the YSI (Yellow Springs Instrument) STAT Plus™ Glucose Analyzer. YSI measurements were

performed in duplicate on venous whole blood and the FreeStyle measurements were performed in duplicate on

capillary blood from the finger. All YSI whole blood measurements were adjusted by applying a +12% correction

factor (based on a normal hematocrit value of 45%).
Users and healthcare providers should consider that performance in this study might be idealized. Participants

enrolled in the clinical study and certain conditions of the study tend to result in above average glucose control.

This, in turn, may result in the appearance that the FreeStyle Navigator Continuous Glucose Monitoring

System agrees with blood glucose levels better than it does under typical conditions. Monitors that measure

glucose in interstitial fluid often show better agreement to blood glucose levels when glucose levels are not

changing rapidly or when glucose levels are not extremely low or high. The following are some examples of why

performance of the FreeStyle Navigator Continuous Glucose Monitoring System may be idealized.

Subjects saw, on average, 15 fingerstick results per day in the clinic and 8 fingerstick results per day at home.

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This enables subjects to control their glucose levels better.
While subjects participated in the clinic portion of the study, they were more limited in their activities than

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someone at home. They were also provided with all their meals. Subjects who are more active, or with poor

eating habits, may create more challenging conditions for the FreeStyle Navigator Continuous Glucose

Monitoring System.
The built-in FreeStyle glucose meters used in the study were well maintained. Because the built-in FreeStyle

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meter is used to calibrate the FreeStyle Navigator Continuous Glucose Monitoring System, performance

may be poorer if the system is not well maintained. It is important to carry out quality-control checks on

the system and code the system according to the manufacturer’s instructions to optimize performance of the

FreeStyle Navigator Continuous Glucose Monitoring System

18 Appendix B: Specifications

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Section 18