Due to the Freestyle test strip recall, we have been using an independent Freestyle meter (with older strips) along with the imbedded Omnipod PDM reader (newer recall replacement strips). Except for one instance where the readings matched, the independent meter consistently produces higher readings than the Omnipod meter.
Given A1C tests, I tend to believe that the independent reader is more accurate, but how do I know for sure? Since the discrepancies are generally lower than 20%, Abbott doesn't care.
Since switching from MDIs (with OneTouch meter) to the Omnipod a year ago, A1C numbers have been somewhat higher than before. Management is good, so shouldn't the A1C be lower (better)?
I really don't want to lug around a meter and the PDM and manually enter BG readings indefinitely, but it seems pointless to work so hard managing sugars if the information is inaccurate.
Does anyone have any advice or suggestions?
Finger pricks show what your blood sugars are doing at that moment. CGMS shows your blood sugars every 5 minutes. Finger pricking is not a reliable way of predicting HbA1C, even with a perfect meter. If you think the meter that reads higher is better, use it.
I would choose a meter that can also test for ketones.
You can test your meter with control solution.
Yes, a control solution is the only real test you can do to a meter for accuracy. If you don't have any solution, ask your pharmacist or doctor.
The meters both pass the control solution test.
What were the numbers that you got with the control solution?
This means that your meter reads low. All my Freestyle meters read low. The perfect reading is exactly in the middle of the control solution range. For my control solution this is 104 mg/dl. I adjusted the code on my PDM so that it reads close to 104 mg/dl with the control solution.
I had a problem with my A1C too: A1C Surprise
So now you use the PDM and an independent meter?
With strips manufactured after the recall I use the PDM with code 18. Works out perfectly for me. With strips manufactured before the recall I had to use code 19. This suggests to me that Abbott adjusted the strips by about 10%. With code 16 the strips manufactured before the recall read more than 20% low. The strips manufactured after the recall read only 10% low which is fine by FDA standards.
Abbott had been sued after many people had died because Abbott meters read high. There is no such danger when meters read low. I expect that Abbott reacted to the lawsuit by changing their meters to read as low as possible within the FDA guidelines. Abbott just overshot a little. I speculate that it was Abbott's business decision to have their meters read low.
helmut, this is what I've done, too. coded PDM at 18 and it matches my other meter(s) and CGM.
I am actually more comfortable with the control solution test. I wouldn't know how to assess whether other meters are correct or read high or low. Comparing to CGM is not a useful test at all. The CGM can at best read the same as the meter that you used to calibrate the CGM.
Did I misunderstand the purpose of the codes? I thought they were to tell the meter what kind of strip was being used. But based on what you've said, it's more of a calibration tool.
Our clinic always told us just to make sure the code on the strips matched the meter.
Did you ever ask Abbott (or Insulet) about this technique?
I remember the time when vials came with codes other than 16. It was rare to get 2 vials with the same number. It was very important that the code on the vials matched the meter. The code quantifies how much the strips deviate from the standard and how the meter should correct for that.
The problem is that the recalled vials should have had code 17 on them, not 16. In other words, these strips were out of spec for code 16, but work fine with code 17.
MY CGM is nearly always correct and matches nearly perfectly to what my blood draws are. If I calibrate CGM to and with PDM using anything other then 18 code, my CGM will just calibrate and reflect higher blood sugars anyway, about 20 - 30 points higher regardless. it will just calibrate higher to what my blood sugars are, which are represented on my contour meter. a control solution test has a high variance, they always test 'correct'.
I've noticed that too. Out of all the meters I've used, I've found that my OneTouch Ultra matches my BG measurements from my blood draws - almost exactly each time. Hence, this is what I use as my calibration tool for my OmniPod PDM.
I will test the same drop of blood on my OmniPod PDM and my OneTouch and then adjust the code on the OmniPod PDM to 16, 17 or 18 depending on what gets me closest to the OneTouch reading - irrespective of what code is printed on the container of FreeStyle strips.