How to estimate your BG meter's noise

[Nickyghaleb]

Kinda like what it feels like, yeah.

[Chris]

In addition to what @Eric has mentioned. Keep doing what you are doing, then when you have your next physicians appointment, right before or after your blood draw take a reading with both meters. Then when you have the lab value you will understand where the meter is for you.

[Nickyghaleb]

I will definitely do that. I appreciate it. Just out of curiosity, is there anywhere else to get a lab draw that you can think of? I’m not due for an appointment for probably another 2 months. I’m not going to have any more blood in my body for that blood draw. i’ll do the research, just thought maybe someone would know another way…

[Chris]

If you are on the good side of your physician, they might order a blood draw that you could do at a blood draw center close to you and get your bg tested. Honestly, would you really change your treatment if you know that your meter trends 10-15 points off your actual blood glucose. If the answer is yes, I would pursue the answer.

[Nickyghaleb]

I have taken so many numbers at this point that I’ve learned how to take them all with a grain of salt… pretty much. BUT there are a couple of things that I need to do because I am who I am (and that is a mentally ill person, I guess, because I don’t know who else would do this)… the MOST important thing is that I use these readings for my calibration factors. I actually use those to make important decisions. Now I do understand their limitations because they’re 100% dependent on my BG reading, and that’s just a problem anyway. But I would want to adjust my thinking… I’m still in the early stages of understanding this stuff, and, yes, I think that particular number would… okay I don’t know. Maybe not. But here’s the OTHER most important thing… I was getting ready to make a video about the Libre. And, honestly, I’m pretty impressed by it. (The Libre). Believe it or not though, I have a little integrity, and I want to put out thoroughly collected and calculated numbers. I collected 30 days’ worth of numbers based on my Relion… it not only showed the Libre to be more reliable, accurate, AND better equipped to handle the lag, but in showing all of that, it also showed just how WEAK the guardian is. The guardian is the only sensor that currently is involved in treatment decisions, and, well, it would be scary to look at these numbers knowing your pump is basing your dose off of them. I do want to make that video, too, though. There’s no doubt in my mind about it as it reflects what my experience has been since starting it, and I started on it using the One Touch. BUT a general difference of 15 really might have some signifance and might make those numbers look different. I have a good solution though, and that is to present my findings and to emphasize the fact I used my Relion. And then to repeat it with either my one Touch or the contour next one I just ordered. And you don’t have to respond to this very long thing here… I sometimes talk to myself through my posts to others, trying to talk myself into it out of a particular thing.

[Eric]

@Chris

Honestly, would you really change your treatment if you know that your meter trends 10-15 points off your actual blood glucose.

If it is 15 points off and says I am 200, nope.

If it is 15 points off and says I am 60, yep.

A 15 point difference ranges from insignificant to huge.

[Michel]

@Nickyghaleb

Last night:
Guardian: 156 (triple arrow up)
Relion: 176
One Touch: 156
Libre: 178 (one arrow up)
I can deal with that… not happy about it, but at least there’s a pattern…

The from this morning:

Before my run (don’t judge… I got side tracked and took too long getting out)
Guardian: 292 (one arrow up)
Relion: 258
One Touch: 220
Libre: 278 (angled arrow up)

After run:
Guardian: 123 (double arrow down)
ReliOn: 114
One Touch 101
Libre: 94 (angled arrow down)

And a little bit later:
Guardian: 134
Relion: 132
One Touch: 102
Libre: 129
And then immediately afterward:
Relion: 139
One Touch: 135

@Nickyghaleb, what you have done with meter accuracy numbers is outstanding!

Some thoughts and a question:

• accuracy numbers far from your range don’t matter much, because you are trying to leave from there asap. So it does not matter if your numbers are spread in the 200 range. The only thing here that matters is that they are precise enough to give you a correction bolus. Even your worst meter when high appears to be good enough.

• the only area where accuracy matters is (a) around 70, because you really don’t want to get hypoinsensitive, and, less but still important, (b) between 70 and 120-130-140, whatever your range is: you are trying to be there all the time, so you’d like to know when you are there. Also, for (b), your corrections need to be more precise, so it is more important to be close.

• My sense is that, when you have a good number of meters, there is a pretty good chance that their overall average is close to reality. But, of course, the more you have the likelier it is, and it is impossible to prove, really.

• Important: when your BG is changing quickly, your interstitial fluid measurement may be way off. So the Guardian and the Libre may be way off for 10-20 minutes when you are going through quick changes. For instance, after my son corrects a fast drop with glucose, his Dexcom will keep on dropping for 15-20 minutes, sometimes down to the 50s or lower, when his real BG may well be above 70 all that time.

So, comparisons when BG is quick moving are almost impossible, and probably not profitable.

When I look at the range of numbers you were worried about, I am not so much. Your 280 range numbers don’t matter. Your after-run numbers must have been varying quickly. Your “little bit later” numbers are reasonably tight, with the exception of the OneTouch. I am inclined to think you were right around 130 at that time.

Question: did you ever check your meters at the doctor’s office? I am curious.

Either way, I was very impressed by the consistency of your Reli-On meter!

[Nickyghaleb]

@Michel, I don’t know if I’m doing this right, but I was trying to show you my lab draw comparison. I still can’t get any Reli-on respect, but it won as far as I can tell.

So Word on FUD Street is Contour is the Meter to go with.... but why?

Okay and now I’m coming around, FINALLY, to update this with my lab draw meter comparison results… and then to listen to you all cry foul if anyone actually comes back through and reads it… I brought 3 meters, My Contour, my One Touch, and my TRUSTY OLD Relion from Walmart at only 17 cents a strip. I tested all three immediately after the tech collected my blood… and then immediately again 2 more times. Just because. First test: [image] Second test: [image] Final test: [image] And my LAB VAL…

I am heading off for bloodwork today. I’ll pack it all up and go for round 2!

[Nickyghaleb]

@Michel

Important: when your BG is changing quickly, your interstitial fluid measurement may be way off. So the Guardian and the Libre may be way off for 10-20 minutes when you are going through quick changes. For instance, after my son corrects a fast drop with glucose, his Dexcom will keep on dropping for 15-20 minutes, sometimes down to the 50s or lower, when his real BG may well be above 70 all that time.

This I understand better than I do my own children. I have looked at so many numbers in the last year and a half, I have finally gotten quite good at being able to estimate a pretty accurate BG based on all of their patterns. I know this is not using the force, as Eric recommends, but I can’t always tell without looking. I’m not consistently unaware; I’m just consistently inconsistent. As long as I have some values though, delayed as they may be, I have a good idea where I stand.

I see reactions to my posts about my meters, but I have good reason for watching numbers the way I do. The best reason is that I find them fascinating. There isn’t a number I write down that isn’t significant. And I write down a lot of numbers. The other reason, however, is the more important of the two, and that is that I have a terrible time with roller coasters. I do pay a lot of attention to my diabetes now, but attention alone isn’t quite enough. I need precise treatment. If I overbolus by a unit or two, I may have already put myself on the next ride. I depend on these numbers to make good decisions, and even being able to identify which numbers probably are not accurate helps me get information from them… which is how I find myself fascinated… by every number I put down.

I want more than anything to do something with the calibration factor, which I mention now because it is an interatitial fluid signal. I’ve talked about it a good deal, but I haven’t started anything yet because I think Medtronic’s sensors that are currently in circulation are no good. As long as the sensors are no good, the factor is all but useless. It’s the other way I control my roller coasters, and that calculation also relies heavily on a good BG meter reading. The great news is many of the readings are good, and those that aren’t as good often have a pattern of their own.

All of this and then I hit a 400 because I forgot to bolus for dinner.

Sorry to drone on. I’ve got a run to take, blood work to do, and bills that I’d prefer not to bother with ever. Not all numbers have such appeal. I hope you have a great day!

[Michel]

@Nickyghaleb, I moved your reply from the Contour thread and included a link to your critical post! The way to do it is:

• go to the post you want to link to

• look at the horizontal menu at the bottom of the post

• in that menu, select the “link” icon (looks like a chain), then copy paste that link into the new post you are writing.

That test was excellent! For the sake of readability, I am summarizing your results here:

Contour Next One: 93-101-100
OneTouch Ultra Mini: 89-94-92
ReliOn: 86-87-86

Lab test: 77

For the clarity, exactly when did you sample your blood vs when the lab sample was taken?

[Nickyghaleb]

@Michel

For the clarity, exactly when did you sample your blood vs when the lab sample was taken?

I sampled my blood the moment she finished, then immediately again, and then a third time which was about 3 or 4 minutes later. Is that what you mean?

Thank you for moving it, and I will try to remember how for next time.

I do another draw today… and am very excited.