@Scott-C How many times a day on average do you think you calibrate xDrip? Do you calibrate against the Freestyle Libre finger prick or another glucometer.
Evening, Joe.
I only used the inbuilt libre bg meter a few times, couldn't be bothered faffing around with the individually wrapped strips. Prefer to use my onetouch verio iq for calibrating as I've it for years now and am used to it. I found the libre bg meter tended to run a bit lower than the iq, different algos, I suppose.
I tend to calibrate about twice a day, sometimes three.
Usually in the morning when I wake, both to set it up for the day, and because (assuming my basal is set ok), I'm likely to be stable and there's a fair chance that because I've been at rest, glucose in ifg will likely be similar to glucose in blood.
Then, sometimes before evening meal, and usually before bed.
Everything I've read on it suggests it's best to calibrate when stable, because if you try to do it when sugars are moving rapidly it'll just end up confusing it. What's the point in bg testing at, say, 5.5 just after a meal, then feeding that in as a calibration, when you may well be at 8 20 mins later - the algo isn't going to know what the 5.5 refers to when getting the signal from the sensor.
I think I made the mistake of calibrating too much when I first got it, mistakenly thinking the more info I gave it the better, but that seems not to be the case. Counter-intuitively, it makes it worse. So, now I keep it down to 2 or 3 and actively avoid calibrating when on a pronounced up or down trend.
I've had a few spells where for a few days it just didn't seem to hold or learn anything from a calibration and would be well out after a few hours. I don't know why that was, maybe a dubious sensor, maybe biology, who knows. I've just learned to accept that when there's so many variables involved sometimes there'll be flyers and I just have to take the rough with the smooth.
William Lee Dubois wrote a short book, couple of quid on kindle, Beyond Fingersticks: the Art of Control with Continuous Glucose Monitoring. It's got a short but useful section on calibrating. It was written around 2009 which is like prehistory in cgm terms so some it is dated now but he still makes a lot of good points which are still valid today about what to expect, and, just as importantly, what not to expect from cgm. A useful read alongside Stephen Ponder's Sugar Surfing.
There's an amusing bit where he's looking into the future from waaaay back in 2009 and imagining the day when people will be able to see cgm
on their phones!