One of my purposes for getting Dex was to cut back on the number of times I test per day. I use way too many strips. However, because I don't trust my numbers on the Dex I find I still test just as much! I know that we must still test before eating, and are not to trust the Dex for calculating boluses. However, there apparently is a 20% margin of error on the Dex, and I find that too much especially when heading for a low. That could mean the difference of a serious problem or just the thought of "oh brother, I'd better eat something." So I get nervous and I test as much as I have always done. I am usually about 20% off in my readings. Occasionally I am pretty close, but not most of the time.
What are your experiences? I REALLY want to cut back on test strips.
I've gotten 15-20 minutes worth of readings 20 feet or more when I forgot it in my bedroom when getting ready in the bathroom... Cheers.
Thankyou for sharing. In dead quiet environment - no RF at frequencies of the dexcom, one can get some surprising distances between transmitter and receiver. Obviously - no guarantee over the 5 foot spec.
I found that by changing my site location, my readings became more accurate. I was about to throw 'Dexie' out the window, when someone suggested switching to a different location. I went from the abdomen/tummy area to my thigh. So often the reading is within 2 to ten points. However, sometimes it can vary more and as I never know when this is, I still average 8 BG tests/day. It is very useful for trends.
Thank you for excellent feedback.
Many have reported on changing from gut (FDA approved sit) to other locations, thighs, arms etc.
For me on gut was over a 100 points off on occasions. On upper arm, readings way better, useable and helpful - gut useless.
Glad to hear you are having better success.
I am going to change site from ab to thigh and see what happens. Will report back. This is pretty interesting stuff, even if frustrating!
Kate- where on your thigh are you going to try? top or outside? I'm a side sleeper so i'm worried about putting it on the outside of my thigh... Thanks :)
For me, it is not a problem on my thigh, even sleeping on my side. I put it on the top and sightly to the outside of my thigh. I keep 'Dexie' in the bed with me, close. Fortunately I don't move much while sleeping.
Upper arm (outside, enough towards the back so it doesn't get bumped) has given me the best readings. Second best is mid-thigh, just clockwise of where your thighs meet with your legs together. YMMV
KateR's point is still extremely valid.
After spending your money or insurance money for cgms, one would truly hope that as a benefit it would trim back the cost of the cave man machine.
At $1000 for base kit plus $ 310 per 4 sensors at worst case - one month, one would truly hope that the cost of caveman machine would be trimmed.
Good luck on that one as we are all fleeced into hades rotting out.
I have been T2 for 25 years, using a Ping Pump for 4 years, and Dexcom for 3 years.
Here is what I have learned:
1) Even in a lab, if a specimen of blood is divided and tested twice, the same machine will give two different numbers. They will be within ± say 2%.
2) Lifescan, not the new Verio IQ, has a ±10% for tests near 100mg/dL, meaning 90-110.
3) Dexcom is ±15%. Remember it is for TRENDS, NOT real numbers.
4) Every time you dose insulin, do a finger stick - DO NOT use the CGM value. This is for SAFETY! Testing is especially true if you are a)very brittle, b) stressed -good or bad, c) have a change in activity, or d) doing anything out of your routine.
5) I have had 5 surgeries in the past 4 years. With my pump and CGM, the recovery and rehab have reinforced every one of these points.
6) Remember, a meter and a CGM are tools. You must use them correctly to get the best results.
7) Understanding how a CGM works helps wrap your head around all of this. There are several parts for the Dexcom. a) the wire acts like a battery - more glucose = more current. b) the transmitter reports the current. c) The receiver analyses and evaluates the current to display a prediction of mg/dL and the trends it is seeing. Look at the formula in the Dexcom book to learn this specifically.
8) Several posts here and on other D sites have indicated failure to use according to manufacturer's instructions have lead insurance companies NOT to pay for "problems" if the item is not used as ordered. The situation was about a Dexcom wire breaking under the skin of the thigh, surgical recovery was required. Insurance would not pay because sensor was to be used on the abdomen, not the thigh. Be careful about the advice you follow to go away from manufacturer's FDA approved instructions - insurance may not pay for problems.
Best wishes - and be a safe user of your tools.