Following the release of the FDA statement about DIY systems, and the implication that it is a DIY CGM that caused the issue (essentially Libre being used with one of the third party adaptors and one of xDrip, Spike or Glimp), I thought it timely to find out how variable the dataset can be.
To put this in context, when I tested Libre against the G6 previously, I wasn’t impressed with the outcomes, and yet, anecdotally I regularly hear that it’s great, and that people get very accurate results.
As a result, I’ve decided that it’s time to run a comparison of the G6 versus the Libre, and split it into four weeks of testing. The set-up will use the 21st May Nightly build of xDrip software running on Android for collecting Libre data.
For each week, I’ll use a different calibration method on the Libre. The four approaches will be:
- Allow automatic calibration in xDrip
- Calibrate once daily
- Calibrate twice daily
- Adjust the slope of the line to 1 and calibrate “as required”
Hopefully using these four different approaches will give some insight into how the data varies under the circumstances of each type of calibration.
These will be run against the G6 operating in “Code-Mode” and not requiring calibrations.
The data will be stored in a test Nightscout instance which will mean that it can then be extracted and quantitatively analysed to try and determine variance, and of course, there’s also a bunch of finger prick tests required, so time to say thanks to my fingers ahead of time!
What do people predict as the outcomes? Which of the calibration strategies will result in the best outcomes? At this stage, I’m not sure, but it should be interesting finding out.