• System includes a receiver/display, transmitter, and subcutaneous sensor.
• Wireless system; radio signals utilized.
• Waterproof sensors/transmitters (receiver/display not waterproof).
• Require periodic calibration with fingerstick blood glucose readings.
• Customizable alarms for high/low glucose values.
• Multiple on-screen trend graphs.
• Arrows indicate rate & direction of BG change
• Mechanical device used to insert sensors.
• Sensors typically re-usable; sensor life varies from person to person.
• Warmup period at beginning of sensor session.
• Some lag time between blood glucose (fingerstick) and subcutaneous glucose (sensor) values.
• Insurance coverage varies from plan to plan.
• Minimal skin irritation, even with prolonged sensor life.

Dexcom Seven

Medtronic RT

Freestyle Navigator

PROS

• Compact sensor/transmitter with excellent skin adhesion
• Virtually no skin irritation
• Lowest system start-up cost (~ $800)
• Lowest per-day sensor cost (~ $5/day)
• Reasonable accuracy (+/- ~15%)
• Free 1-time replacement of system components (within 1-yr warranty)
• Avg. sensor life 12-14 days
• Flexible calibration times
• Very loud alarm (vibrates prior to alarm)
• Large, well-lit screen

• Does not require separate monitor (if using compatible insulin pump)
• Compact sensor/transmitter
• FDA-approved for children
• Re-usable sensor insertion device
• Data downloadable to online program; detailed analysis & excellent graphics
• Can scroll through specific data points on trend graphs
• Transmitter "remembers" last 40 minutes of data if out-of-range of receiver
• Predictive alerts (Guardian model)
• Reasonable per-day sensor cost (~ $6)

• Best overall accuracy (+/- ~14%)
• On-screen data updates every minute; shortest data lag time
• Detailed on-screen analysis w/stats
• Many trend graphs w/ scroll-back feature
• Separate target BG and alarm ranges
• Meter built into display/receiver
• Highly customizable high/low alerts and predictive alerts
• Greatest transmitter signal range
• Nothing to charge; all disposable batteries
• Fewest calibrations required (4 per 5 days)
• Avg. sensor life 7-10 days
• Simplest sensor insertion process

CONS

• Must charge receiver every 3-5 days
• Limited options for high/low alarms
• Data spikes w/acetaminophen
• On-screen data update every 5 minutes
• Cannot scroll back in time to specific data points
• Download to PC is time-consuming; low quality graphics
• Very loud alarm
• Sensor insertion requires some practice
• No data collection when out of transmitter range

• Poorest overall accuracy (+/- ~ 19%)
• Avg. sensor life 4-6 days
• Sensor/transmitter requires tape covering
• Alarms may go unnoticed
• Transmitter requires charging at least every 6 days
• Stops showing data if calibration missed
• Relatively small screen
• Requires sensor change/restart every 3 days
• On-screen data update every 5 minutes
• Requires 2-3 calibrations per day
• Should not use "Link" meter with pump when sensor is in use
• Effective sensor insertion is highly technique-dependent
• May only calibrate when BG stable & within specified range

• Bulky sensor/transmitter
• Poor Skin adhesion; extra tape often needed
• Perpendicular sensor may cause irritation in lean individuals
• 10-Hour warm-up period with each sensor startup.
• Repeated alarms with high & low glucose levels may be a nuisance.
• On-screen text difficult to read without backlight
• Must go through several menus to get to trend graphs
• Highest start-up cost (~ $1200) and per-day sensor cost (~ $9/day)
• Calibration times require scheduling
• Must use Freestyle strips for calibrating
• May only calibrate when BG stable & within specified range