Tuesday, June 13, 2017

Glucose meters, WTF?

Enhanced version of my original Facebook post

Been using a True Test meter just to keep an eye on things every week or so since mid 2013. This is because I read at the high end of OK on the yearly physical blood panel that you fast for. Doc was worried my reading might be higher when not fasting but they do not seem to be. Pretty steady readings. (Excluding off diet days ) Should note I took a reading right before the blood panel each year to check meter's accuracy and the reading would always be real close.
Anyway recently I ordered what I thought were the right replacement strips but they are for a newer True meter model. The packaging looks almost the same. After some research I discovered my type strips had been pulled from the market because they did not meet new accuracy regulations. (FDA says they now have to be within 15% instead of the previous 20%) So I did more research to see what new meter I should get. I finally settled on the FreeStyle Lite which Consumer Reports, among others, said was more accurate and had highest repeatably. When I tried it though I was shocked how high my readings were. OK not call the doc high but but the chart here shows how things got a lot less steady on May 19th. Doc had me on some short term inflammation meds known to raise BP and glucose though so I just checked it every day or 2 till after I was off the meds. But the readings were still higher than I was used to after the meds ended on the 22nd. So I bought test solutions to check the meter. The readings with the test solutions varied widely too. High solution was 346 to 281 and low was from 65 to 43. You might notice my readings for Jun 5th are 120 and 7 minutes later 111. Which seems off but is within the 15% guideline. The test solutions however are not even close.

So I just ordered two more meters. The other top rated Bayer Contour Next and the one that matches the strips I got by mistake, a True Track. The test solutions are good for a couple more months so when the new meters get here I'll test all 3 side by side with the same drop of high and low solutions to see just how close they are. I only wish I still had a few strips for my old meter to compare with.

How I did testing

The new meters came with test solutions so I had 4 to try. I also found that maybe I did not shake the solutions enough in the tests above. This time I gave each 20 flips before putting 5 drops in a spoon. I then sampled each with meter in rotation, just in case testing some how tainted the solution. I did 2 tests with each meter in each solution. I would have liked to do more but the Bayer only comes with 10 strips and did not want to buy a bunch more if the meter is useless.

Each vial of test strips is labeled with what to expect when you test with. Here is what these test strips should report. I've highlighted the solutions I had to test with.

Strip Ranges
Contour Next EZFreestyle LiteTrue Track
lowhighlowhighlowhigh
Level 13746
Level 2111138
Low3060
High248372
True Control 084114
True Control 1175237
True Control 2361489

The disappointing results

Here are the readings I got. The ones in range of what they should be are in green

Readings
Contour Next EZFreestyle LiteTrue Track
Freestyle low3680140
Freestyle low (2)3849130
Contour Next lvl 212468267
Contour Next lvl 2 (2)12973264
Freestyle high182283Hi (>600)
Freestyle high (2)183296Hi (>600)
True Control 17998230
True Control 1 (2)73103211
So I just do not know what to make of this. Interestingly other than one reading they all are in range when tested with the same brand solution but only the Bayer was in range with someone else's solution. So my first thought would be the Bayer though it is readings seem low. I guess the thing to do is get more Bayer strips and check my blood with all 3 meters for several sessions. Given the above results I'm not sure if any of these meters tells me anything about my glucose levels. I'll update this again after I get a few readings.

One last thing. As I mentioned above the FreeStyle Lite Blood Glucose Test Strips are the most expensive at $74.50 for 100 and it appears Amazon has stopped carrying them. The TRUEtrack Blood Glucose Test Strips come in at 100 for $20 and Contour-Next Contour Test Strips come in at around $21 for 100.

Update 6/17/2017: First blood test. I got a drop of blood on my finger large enough to do 2 rounds of tests with the meters. First round

Second round

 To me the interesting bit is even though the Bayer and TrueTrack meters vary 8.41% and 12.26% respectively but they both vary in the same direction which would tend to make me think there might actually be that much variance in the blood sample itself. Let's look at the data again.

Readings
Contour Next EZFreestyle LiteTrue TrackAverageStandard DeviationMeanMin from max
Freestyle low368014085.3352.2080.00388.89%
Freestyle low (2)384913072.3350.2449.00342.11%
Round deviation5.56%63.27%7.69%
Avg for meter / average for test53.07%18.18%71.25%
Avg for meter / min for test2.78%79.17%275.00%
Contour Next lvl 212468267153.00102.62124.00392.65%
Contour Next lvl 2 (2)12973264155.3398.19129.00361.64%
Round deviation4.03%7.35%1.14%
Avg for meter / average for test17.95%54.27%72.22%
Avg for meter / min for test86.03%3.68%290.44%
Freestyle high182283600355.00218.10283.00329.67%
Freestyle high (2)183296600359.67215.67296.00327.87%
Round deviation0.55%4.59%0.00%
Avg for meter / average for test48.93%18.98%67.91%
Avg for meter / min for test0.27%59.07%229.67%
True Control 17998230135.6782.2598.00291.14%
True Control 1 (2)73103211129.0072.58103.00289.04%
Round deviation8.22%5.10%9.00%
Avg for meter / average for test42.57%24.06%66.62%
Avg for meter / min for test4.11%37.67%202.05%
Blood test 1 sample 1107143106118.6721.08107.00134.91%
Blood test 1 sample 2116135119123.3310.21119.00116.38%
Round deviation8.41%5.93%12.26%
Avg for meter / average for test7.85%14.88%7.02%
Avg for meter / min for test5.19%31.13%6.13%
Avg for meter / max for test6.64%12.59%5.94%
Average Round deviation (repeatability)5.35%17.25%6.02%
Average of averages25.03%26.07%57.00%

Repeatability wise Bayer seems to be best by a bit and best all around. Especially when you consider second place for  Repeatability is TrueTack and over all is Freestyle.

Something else I just noticed it the strip I just received for the Bayer meter have different ranges than the first ones that came with the meter.


Lastly I realized I had not said anything about the kits the meters come with.  Here are pics of them. The Bayer and TrueTrack came with test solutions and the Freestyle did not. I bought those separately.

The Freestyle

The Bayer 

And the TrueTrack

The Bayer kit seems not thought out to me. Especially given the meter seems the most accurate so far. Personally of the 3 lancet devices I prefer the TrueTrack one. It is easier to use and seems to get a larger sample for the same setting.

UPDATE: 8/5/2017 Added 6 more days worth of tests and some more color coding.

The Contour is still the one closest to the average of all 3 meters and seems the most repeatable

Readings
Contour Next EZFreestyle LiteTrue TrackAverageStandard DeviationMeanMin from max
Freestyle low368014085.3352.2080.00388.89%
Freestyle low (2)384913072.3350.2449.00342.11%
Round deviation5.56%63.27%7.69%
Avg for meter / average for test53.07%18.18%71.25%
Avg for meter / min for test2.78%79.17%275.00%
Contour Next lvl 212468267153.00102.62124.00392.65%
Contour Next lvl 2 (2)12973264155.3398.19129.00361.64%
Round deviation4.03%7.35%1.14%
Avg for meter / average for test17.95%54.27%72.22%
Avg for meter / min for test86.03%3.68%290.44%
Freestyle high182283600355.00218.10283.00329.67%
Freestyle high (2)183296600359.67215.67296.00327.87%
Round deviation0.55%4.59%0.00%
Avg for meter / average for test48.93%18.98%67.91%
Avg for meter / min for test0.27%59.07%229.67%
True Control 17998230135.6782.2598.00291.14%
True Control 1 (2)73103211129.0072.58103.00289.04%
Round deviation8.22%5.10%9.00%
Avg for meter / average for test42.57%24.06%66.62%
Avg for meter / min for test4.11%37.67%202.05%
Blood test 1 sample 1107143106118.6721.08107.00134.91%
Blood test 1 sample 2116135119123.3310.21119.00116.38%
Round deviation8.41%5.93%12.26%
Avg for meter / average for test7.85%14.88%7.02%
Avg for meter / min for test5.19%31.13%6.13%
Avg for meter / max for test6.64%12.59%5.94%
6/24/2017107125104112.0011.36107.00120.19%
6/24/2017108123123118.008.66123.00113.89%
Round deviation0.93%1.63%18.27%
Avg for meter / average for test6.52%7.83%1.30%
Avg for meter / min for test3.37%19.23%9.13%
Avg for meter / max for test6.00%7.20%1.20%
6/25/2017110113105109.334.04110.00107.62%
6/25/2017105124123117.3310.69123.00118.10%
Round deviation4.76%9.73%17.14%
Avg for meter / average for test5.15%4.56%0.59%
Avg for meter / min for test2.38%12.86%8.57%
Avg for meter / max for test4.70%4.17%0.54%
7/1/2017113132102115.6715.18113.00129.41%
7/1/201710910497103.336.03104.00112.37%
Round deviation3.67%26.92%5.15%
Avg for meter / average for test1.37%7.76%9.13%
Avg for meter / min for test14.43%21.65%2.58%
Avg for meter / max for test1.14%6.44%7.58%
7/2/2017112112109111.001.73112.00102.75%
7/2/2017109122106112.338.50109.00115.09%
Round deviation2.75%8.93%2.83%
Avg for meter / average for test1.04%4.78%3.73%
Avg for meter / min for test4.25%10.38%1.42%
Avg for meter / max for test0.96%4.37%3.42%
7/9/201799106104103.003.61104.00107.07%
7/9/201710210397100.673.21102.00106.19%
Round deviation3.03%2.91%7.22%
Avg for meter / average for test1.31%2.62%1.31%
Avg for meter / min for test3.61%7.73%3.61%
Avg for meter / max for test1.26%2.52%1.26%
7/16/2017104103101102.671.53103.00102.97%
8/4/2017107101109105.674.16107.00107.92%
8/4/2017107100121109.3310.69107.00121.00%
Round deviation0.00%1.00%11.01%
Avg for meter / average for test0.47%6.51%6.98%
Avg for meter / min for test7.00%0.50%15.00%
Avg for meter / max for test0.41%5.79%6.20%
Average Round deviation (repeatability)3.81%12.49%8.34%
Average of averages11.75%16.92%47.51%
LegendReading in range for test solutionLowest value of 3
Calculated valueHighest of 3
Reading with 5 of average
The pics of the new tests













2 comments:

  1. Added first test with real blood and more info.

    ReplyDelete
  2. Added 6 more days worth of blood tests and some more color coding to table.

    ReplyDelete