I asked last night for someone to call me back after my Navigator fingerstick and Navigator CGMS were reading 90 points off. I learned two very interesting things - 1 fact and 1 "major speculation" on our part. I spoke with one of their CDEs, and she said she has worn it before. 1) If your fingerstick on the Freestyle is 20-49.9% off of the CGMS reading, that is a good time to FORCE a calibration. The documentation says only to do it if the helpdesk people tell you, but she said that definitely, if its that far off, then to do it. She said it tells you that it will "wipe all" data. This is important to know because she says that the last 2 days are supposed to be the MOST accurate because the algorithm takes all of the calibrations and readings over the previous 3 days to do the "readings". Forcing the calibrations loses that data, but forcing the calibration should get it back on track within 20 minutes. 2) And this is purely speculation on my AND Her part, and I asked her if she would research it more. I "appears" if you do a fingerstick using the built-in meter, than the CGMS factors that in to determining the readings. Last night, Emma had stayed flat at 116 for 90 minutes, and the minute I did a fingerstick with the built-in, her readings started going UP. The CDE said that the engineers said it didn't, BUT, she said she personally has observed the same thing AND that the only people that seem to call with major discrepancies are ones who AREN'T using the built in meter. So, those that are using the built-in meter seem to have more accurate readings, meaning that it HAS to be factoring in those regular BG readings into the formula. I asked her if she could look into that further because that's very interesting to me, and that I wouldn't be using the meter full-time as ours is a meter/remote, but I will use it more if I'm seeing numbers that are "off' and don't want to force a calibration. I wish I had been told it was ok to force a calibration last night.