I recently set out to compare the two meters since I like to have a back up meter to the Contour Next meter supplied by Medtronic. It is only until recently that AETNA started to approve the Contour Next glucose test strips through my insurance coverage.

So I have been using the ONETOUCH UltraMini for the last 5 years or so since it was the only meter that was fully covered by my insurance without a co-pay on my part.

The difference in readings was all over the place, but the only discernible pattern was that the Contour next Link 2.4 meter read consistently higher than the ONETOUCH UltraMini.

I personally think that the Contour Next is a more accurate meter (closer to the real blood glucose number) but the ONETOUCH UlraMini is more precise (multiple readings from one site are closer).

And this is important since the ONETOUCH UlraMini and ONETOUCH Verio’s superior precision is  key to reducing Auto Mode and sensor errors and especially eliminating the “BG Required Loop” that occurs in Auto Mode.

An “Unscientific” Comparison

The reason I say this is an “unscientific” comparison is because, in a lab setting I would have to measure each reading at least three times (triplicate) for statistical purposes. But in my short study here I am more interested in seeing whether there are any trends that can be observed when it comes to comparing measurements performed using these two meters.

As you can see, the Contour next Link seems to measure consistently higher than the UltraMini over the range of my measurement.

CONTOUR NEXT LINK
ONE TOUCH ULTRA MINI
VARIANCE
98
75
23
105
96
9
110
99
11
112
94
18
126
118
8
134
124
10
141
118
23
144
122
22
145
125
20
148
129
19
155
145
10
177
149
28
179
172
7
188
163
25
199
177
22
200
183
17
205
174
31
211
189
22
259
247
12
AVE
18
STDEV
7
%STDEV
41

*all measurements in mg/dL

However, no discernible pattern can be seen for the variance meaning it would be hard to adjust one meter’s reading for the other.

One thing I must say is that I have been able to achieve my Hba1c goals while using the both meters so I do think both meters are accurate enough.

Based on my experience and long-term use, I think the Contour next Link is more accurate (closer to the true reading) while the ONETOUCH UltraMini is more precise (more consistent readings).

Surprisingly, in relation to calibrating the Medtronic MiniMed 670G, I have had better luck with the ONETOUCH UltraMini (probably due to its precision) over the Contour next Link supplied by Medtronic.

UPDATE 09/19/2018: I  am having great luck calibrating for Auto Mode using the ONETOUCH UltraMini or the OneTouch Verio over the Contour next Link. At the back of my mind though is the fact that I know that the OneTouch meters are not as accurate as the Contour next Link.

Using the ONETOUCH Verio to calibrate the Medtronic Minimed 670G

The Guardian sensor numbers are awfully close to the OneTouch numbers during calibration which leads me to question whether the Contour next Link despite its accuracy is the best meter to use for calibration. Obviously it would mean a lot of rework if Medtronic was to move away from the Contour next Link since the meter is the standard way of uploading data to Carelink.

Many people have reported online that they think the Guardian sensor under-reports its numbers by close to 20 mg/dL. I think this might be true based on my recent experience. Dilemma is that the 670G seems to conservatively target your glucose numbers to between 120 and 150 mg/dL.

So if it under-reports, it means that it is very likely for your HbA1C to be above 7.0 if your daily average is in the 120-150 mg/dL range.

I am looking forward to seeing my next HbA1C number and will update accordingly.

UPDATE 10/15/2018: HbA1C was 6.8 exactly where my Endocrinologist wanted to see it. Because I am susceptible to severe hypoglycemia, my HbA1C goals were set a little higher.