Calibrations for Multiple devices

I’ve been noticing of late that our Clarity report is showing a LOT more calibrations than we are actually doing. We only two TWO per day…with some extras in there when it’s off by 20%. However our calibration rate in Clarity is showing an average of 5.6 daily!!!

So, my question to everyone is…SHOULD the fact that I’m calibrating two different devices (iPhone / CGM) for each calibration period result in two entries within Clarity? I mean, logically it makes sense since we are using two devices…both paired separately, but if it’s the case that calibrating separate devices causes duplicate “C” entries within Clarity, then I think this is something they should work to fix.

Is anyone certain whether this is the case or not? If this isn’t the case then I don’t know why our calibration rate shows 5.6. We only do two per day period unless there are times when the reading on the receiver is 20% or more off from his actual BG.

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What you are doing with calibration is calibrating the {sensor, transmitter} at the transmitter.

So, when you calibrate from both devices (PDM, iPhone), you really are calibrating twice as many times as you should. It does not matter from which device you calibrate since you really are calibrating the transmitter.

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But if I do not calibrate separately, the blood drop will never disappear. I mean, I’m saying that but I’ve never tested that theory…so you’re saying if I calibrate only on one of those devices, the blood drop should disappear from the other device?

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If you are using the receiver AND an iPhone, then you only need to calibrate the one device (I would choose the iphone). That calibration is carried over and should be reflected on the other device. I have noticed that it could take 10-15min before showing on the other device.


Thanks guys! This is obvious now that I think about it since the “calibration” is occurring to the sensor/transmitter and not the actual phone/pdm. Some things should be so obvious but they just aren’t to me. Glad I got this cleared up! Now my calibration number should cut in 1/2. lol.

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I had only learned that after a bit of trial and error and talking to the app creator directly.

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I feel the same about many things when I talk to my wife :slight_smile:

I think each of us has a certain type of common sense, well adapted to a set of circumstances, but not always to “everything.” Our mental models are better for some things than for others :slight_smile:

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Because I was calibrating with both the receiver and the iPhone…so they were both making entries into clarity. As pointed out, the calibrations are showing what’s occurring with the transmitter, not the receiver(s). Since I was doing two “hits” on the transmitter per calibration period (once per receiver, once per iPhone), they were both making into clarity.

If my response didn’t answer your question, I’m not sure what your question is!

It’s kinda amazing how a calibration from the receiver can sync with the transmitter, then sync with the iphone, then sync with the dexcom servers. Pretty cool.


@Bradford - Thanks for the simple explanation. So I tested it and it didn’t work. Last night I put a calibration into the Dexcom G5 receiver. However the calibration never showed up in Clarity. The BG data points from the Dexcom app running on the iPhone showed up in Clarity (3 hr delay as expected for Clarity) but not the calibration from the receiver. Although from the app if you go to device info (I think that was the screen) then it does show the calibration time accurately. So I don’t know. If the calibration from the Dexcom receiver gets into Clarity for one person but not for another person then my best guess is “versions” of something involved in the process are in play.

Bottom line is we almost always put the calibration into the iPhone (and NOT the receiver) because we want them to show up in Clarity and it is simply easier/faster to enter the calibration data. The Receiver does recognize the calibration when entered into the iPhone (as you would expect) so no apparent downside.

Did you download the receiver to the Clarity server? I bet if you do that, it will show up.

I did not but would be shocked if you were not correct. Other than for such a test, I would not bother with loading the Receiver data into Clarity as the iPhone already loads continuously into Clarity and it has far far better coverage of the data than the Receiver.

I mostly use the Receiver at night as a redundant alarm device. During the day the Receiver is often out of range. The iPhone would not typically be out of range (day or night) and even if it is, not that long. So when the iPhone comes back in range, it backfills the missing data points which the Receiver can not do.

I am still wondering if the new Dexcom touchscreen receiver (not yet released) will have backfill capability. It would seem crazy for Dexcom to release a new receiver and NOT include that technology.


I, too, have found some inconsistencies when calibrating with the receiver. We always calibrate with the iPhone now, but have had intermittent success with the receiver in the past.