[Papa Diva]

My meter is a One Touch Verio and the second meter is a One Touch Ultra 2

My meter read 132 and the Ultra read 117. Same sample site, one right after the other, mine first. I only did it the one time. I have another Verio on the way with some control solution. Should be here next week. I will update when I get it in and test both.

I have both of those meters as well. I find the Verio to consistently read high. It ranges between 20-50 points higher than the Ultra2. The other thing I noticed is that the higher the BG reading, the more that the Verio is off (higher). I tend to believe the Ultra2 and assume it is within 5-10 points (lower) of reality. I do not trust the Verio at all. Not only is it high, it's not consistent.

One suggestion if you are going to test with two meters at the same time, is to use the same drop of blood when you test. Meaning get a big enough drop to feed both strips. The removes any potential variation from different blood drops.

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[Papa Diva]

What I've found over the years in regards to meters, control-solution meter tests and strips:

First, meters and test strips are affected by temperature. A test in January won't be the same as in July unless the meter and test strips are in a home with a controlled environment. I've tested on a January morning with the temperature in the room at around 55ºF (12.7ºC) and gotten a test value of 136mg/dL. I then put the meter and strip bottle against my skin for a half hour and retested. 114mg/dL. Temperature consistency in your equipment, in my opinion, is key here.

Second, control solution and how I use it. Unlike quasi-homogeneous whole blood...the control solution is a constant. If you take 5 tests with the control solution and any of them don't match...it's not the control solution.

Your Owners Manual will instruct you on how to use the control solution and what is acceptable. They'll tell you that if the test falls in between the range set on the test strip bottle...the meter is within spec's. Not good enough for me.

If my test-strip bottle says the "control range" is between 107-143 mg/dL...that means that in their test of those strips...125 mg/dL was the value they came up with...and 107-143 is their 15% error rate they're allowed.

Here's what I do to test the meter and adjust my whole blood test values. Now, like I said...you have to have a constant temperature range for this to be valid. Let's say my test strip bottle control range is 107-143 mg/dL. That means that when I use the control test solution with one of those strips that the value should be 125 mg/dL. If the test comes up 120 mg/dL...that's means I should add 5 points to any blood test. If it comes up 130 mg/dL...I subtract 5 points.

If you're testing around 200 mg/dL...a 10 to 20 point difference on your meter isn't going to matter. If you're testing down around 60 mg/dL...a 10 to 20 point difference could kill you. Jus' sayin'!

My methodology...no one else's.

That's an interesting approach. I will experiment with that.

What I have done is to test simultaneously with the meter and a lab blood test. This way I use the lab as the baseline so as to see how well the meter precision is compared to the lab. When I have done this, I actually have tested with both a finger stick blood drop AND getting some of the venous blood from the lab technician that goes into the tube. Once I have a baseline, I can then test with the other meters to see how they do to the one that was validated against the lab.

The issue I am trying to figure out is that between 6 meters I have been testing, the deltas between them is troubling. Some of them are consistent, but some have not only big differences, but are also inconsistent.

For example, the Ultra2 and the Relion prime are consistently 5-8 points apart (the Relion is 5-8 points higher than the Ultra2) every time for 100+ tests. The Verio is not only way high, the delta is inconsistent and tends to widen when the BG level is higher.

So using control solution may or may not provide the insight needed. I will test your theory though. For me the only sure way is validate against a lab test.
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[Snorebaby]

That is troubling that the Verio seems to read high. I will test all 3 meters when I get the new Verio with the control solution. I like the idea of using the lab as a baseline. I will see if they will allow me to do that the next time they draw blood.

Thanks for all the suggestions.

 

[smorgan]

Somebody somewhere suggested something which I think is worth a try.

*Get control solution for each meter.

*Take readings with all meters you want to test (3 readings each)

*Take average of all three or, if there's an obvious outlier, average the other two.

*Calculate how much higher or lower this average is from the mid-point of the "acceptable range" for the test solution.

Take a lot of readings with the two meters and record in a spreadsheet, recording the actual and the "corrected" reading for each meter.

I don't have access to control solution right now, but I'd really like to see results from such a test.

I don't know, maybe they'll prove just as flakey, but if not, THIS is what the meters themselves should do. The control solution would actually have a purpose!

 

[Snorebaby]

smorgan....that is the method I am taking. I get my new meter and the control solution on Wednesday, so says UPS. The 3 meters I will test are my MIL's meter, my original meter and the new meter. I will post the tests and results in this thread.

I will have to make a new column in my spreadsheet to accomodate the "corrected" readings.

I have already been working on my spreadsheet addition to show the testing with the

Control Solution Lot #
Test Strip Lot #
Test Strip Readings Range
Test Strip Median
Test Date
Meters Tested
Actual Meter Readings (3x)
Average Meter Reading
Test Strip Median Deviation.

I Guess that might be enough info to back up my testing and information?

 

[smorgan]

smorgan....that is the method I am taking. I get my new meter and the control solution on Wednesday, so says UPS. The 3 meters I will test are my MIL's meter, my original meter and the new meter. I will post the tests and results in this thread.

I will have to make a new column in my spreadsheet to accomodate the "corrected" readings.

I have already been working on my spreadsheet addition to show the testing with the

Control Solution Lot #
Test Strip Lot #
Test Strip Readings Range
Test Strip Median
Test Date
Meters Tested
Actual Meter Readings (3x)
Average Meter Reading
Test Strip Median Deviation.

I Guess that might be enough info to back up my testing and information?

Great! I look forward to it. This is work the meter companies should be doing and providing calibration facilities for their meters. But, the government has made them too comfortable with their allowed TWENTY PERCENT margin of error.

 

[Papa Diva]

Great! I look forward to it. This is work the meter companies should be doing and providing calibration facilities for their meters. But, the government has made them too comfortable with their allowed TWENTY PERCENT margin of error.

Actually, The requirements for accuracy changed last year to a lower tolerance. Now the US FDA requires that results from both consumer meters and clinical labs be more accurate --> +/-15% for home-use meters and a tighter +/-10% for clinical meters.

FDA Tightens Up On Glucose meter Accuracy

There have been a number of discussions on meter accuracy. In addition, there are a number of tests that have been done on multiple meters. Most have been testing meters against each other. Here are two:

BG Meter Accuracy: 10 Popular Meters Put to the Test!

https://medium.com/@chrishannemann/...term-diabetes-control-9caac073dae9#.pc1d272hc

One of the issues is that different meters use different technical methods to "test" the blood by creating electrical impulses that generate a reading. In addition, most use different enzymes to do the testing. I have not figured it all out, but there seems to be some correlation between the enzyme being used and a higher or lower reading. I also wonder if a persons blood chemistry has any play.

I find the use of control solution to be interesting, but since there is a pretty wide range stated on the solutions, I am not sure how to correlate a solution reading to a true BG reading. Bounty's idea is interesting, but I believe that the only true test is to compare the meter to a lab drawn blood test. All labs should allow this.

I do my stick at essentially the same time as the fill the tube. I have also had the lab tech use a butterfly to fill the tube and then get some of the blog from the tube into the test strip.

I have actually seen a small delta between the finger stick (capillary blood) and the venous blood.

When I tested my Ultra2 last time the finger stick was about 8 points low and the venous blood was dead-on the same as the lab.

Doing this a couple of times will tell you 1) if the meter is consistent, and 2) it's delta to your lab BG. If the meter is both consistent and accurate, you can use this as the baseline. I still want to do 1 or 2 more lab comparisons to be sue of accuracy. But today, I use the ultra2 as the baseline against the other 5 meters I have been testing.

I have determined the Ultra2 and Ultra Mini are consistently the same. I am testing against the Ultra2 the following meters: Ultra Verio, Contour Next, CVS, TrueMetrix, and Relion Prime. Unfortunately, the Freestyle and AcuCheck meters are just too expensive for me to throw into the mix.

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[Papa Diva]

The more I think about it, while the control solution is useful, it cannot tell you how precise/accurate a meter is to reality. The only way I can logically see a way to validate is to test against a lab test.

I believe that the assumption that the meter or solution is accurate is flawed as a method of testing preciseness.

Moreover, there is no calibration capabilities on any of the meters, so the solution is not calibration, it only provides a very wide range that is essentially useless as an indicator of accuracy or precision.

We must also consider that the strips are a factor in all of this. They are the weakest link as they can be effected like lost of things. -- Different lots, temp, etc., are also a significant factor.

 

[Snorebaby]

Great info Papa Diva!

I have to agree with you that using the venous blood and comparing it to your lab results is the best method. Then your stick site can be measured at the same time. That will be the closest to accurate as the lab work and that is what the Dr. relies on.

The control solution is supposed to have a consistent amount of glucose. The testing method that smorgan mentioned I believe is the closest you will get to accurate for home use.

From the website for One Touch:

You should perform a control solution test:

Whenever you open a new vial of test strips.
If you suspect that the meter or test strips are not working properly.
If you have had repeated unexpected blood glucose results.
If you drop or damage the meter.

If you get the average reading and use the median of the test strip range as the "calibration standard", I believe it will be more accurate and you can compare that to the lab. The range on my strip vial right now is 102-138. That's 36pts! That is way too much of a variance and could be dangerous in certain situations.

I am new to this and wanting to get the most accurate readings as possible. What prompted me to do this is the differential readings I got when using my Verio to my MIL's Ultra 2. I am 12-15pts higher on my Verio using the same stick site. As I am in the beginning stages of learning how to control my BG, that is a big swing.

Keep the discussion going! I love it!:biggrin:

 

[smorgan]

The more I think about it, while the control solution is useful, it cannot tell you how precise/accurate a meter is to reality. The only way I can logically see a way to validate is to test against a lab test.

I believe that the assumption that the meter or solution is accurate is flawed as a method of testing preciseness.

Moreover, there is no calibration capabilities on any of the meters, so the solution is not calibration, it only provides a very wide range that is essentially useless as an indicator of accuracy or precision.

We must also consider that the strips are a factor in all of this. They are the weakest link as they can be effected like lost of things. -- Different lots, temp, etc., are also a significant factor.

Maybe, but I have never, ever observed any difference between batches of strips. The better quality meters appear to be quite "precise" just not calibrated. I'm assuming the test solution has a certain "real" value but since the government allows 20% range, that's what they specify as the huge "acceptable" range. Dead in the middle of that range should be the "real" BG reading for that solution. In fact, if you look at the range it actually is two endpoints representing 20% error from the mid-point. In other words if you tested that solution with some actually accurate lab test, it should test exactly in the middle of the supplied range.

So, if a meter is indeed precise but only in need of calibration, the test solution may actually have a purpose. Just establish how far and in which direction the meter is off with regard to the actual glucose level of the test solution (the middle of the supplied range). Then, from that point forward, add or subtract the appropriate number from meter readings to get the corrected figure. I believe chances are good that this adjusted number will be MUCH closer to reality and serve as calibration of the meter leaving only random noise or actual inaccuracy inherent in the meter, which for the better ones anyway appears to be MUCH less of a problem than the calibration issue.

One outstanding tricky question, however, is whether the correction should be an absolute number of points or a percentage error. For those of us with BG between 80 and 120 it probably doesn't make that much difference but for bigger numbers it could be significant.

 

[Snorebaby]

The more I think about it, while the control solution is useful, it cannot tell you how precise/accurate a meter is to reality. The only way I can logically see a way to validate is to test against a lab test.

I agree 100%

I believe that the assumption that the meter or solution is accurate is flawed as a method of testing preciseness.

Moreover, there is no calibration capabilities on any of the meters, so the solution is not calibration, it only provides a very wide range that is essentially useless as an indicator of accuracy or precision.

We must also consider that the strips are a factor in all of this. They are the weakest link as they can be effected like lost of things. -- Different lots, temp, etc., are also a significant factor.

Again I agree....but the solution is more constant. It is easier to make a liquid constant than the test strips. I don't know if the solution shows a known value or gives a range as I haven't received mine yet. But it should be tighter than the test strips. I believe the meter only tests what it sees and the biggest variable is the strip itself.

 

[smorgan]

Great info Papa Diva!

I have to agree with you that using the venous blood and comparing it to your lab results is the best method. Then your stick site can be measured at the same time. That will be the closest to accurate as the lab work and that is what the Dr. relies on.

The control solution is supposed to have a consistent amount of glucose. The testing method that smorgan mentioned I believe is the closest you will get to accurate for home use.

From the website for One Touch:

You should perform a control solution test:

Whenever you open a new vial of test strips.
If you suspect that the meter or test strips are not working properly.
If you have had repeated unexpected blood glucose results.
If you drop or damage the meter.

If you get the average reading and use the median of the test strip range as the "calibration standard", I believe it will be more accurate and you can compare that to the lab. The range on my strip vial right now is 102-138. That's 36pts! That is way too much of a variance and could be dangerous in certain situations.

I am new to this and wanting to get the most accurate readings as possible. What prompted me to do this is the differential readings I got when using my Verio to my MIL's Ultra 2. I am 12-15pts higher on my Verio using the same stick site. As I am in the beginning stages of learning how to control my BG, that is a big swing.

Keep the discussion going! I love it!:biggrin:

Testing venous blood with a meter makes no sense. They have a built-in correction factor (calculation) to 'translate' from the capillary reading to what should be the venous reading. They are always different by a fairly predictable amount. In order to simplify things, all the meters built in this correction several decades ago in order to approximate a venous blood reading as closely as possible. So, if you test venous blood with a meter, the built-in correction is inappropriate and the result won't mean much.

 

[Snorebaby]

Testing venous blood with a meter makes no sense. They have a built-in correction factor (calculation) to 'translate' from the capillary reading to what should be the venous reading. They are always different by a fairly predictable amount. In order to simplify things, all the meters built in this correction several decades ago in order to approximate a venous blood reading as closely as possible. So, if you test venous blood with a meter, the built-in correction is inappropriate and the result won't mean much.

Didn't know that! Great Info! Thanks!:thumb:

 

[Snorebaby]

OK. Got my new meter with control solution today. So I did the testing described earlier in this thread. Here are the results:

Test Solution is the Mid-Level (Level 3) from One Touch.

Original Meter - One Touch Verio
Test Strip Range 102-138. (Median 120) Lot # 4014397
Test 1 - 123
Test 2 - 125
Test 3 - 121
Test Average - 123
Meter Variation from Median - 3

New Meter - One Touch Verio
Test Strip Range 102-138. (Median 120) Lot # 3900006
Test 1 - 119
Test 2 - 118
Test 3 - 123
Test Average - 120
Meter Variation from Median - 0

Right now there is not a big variation in average readings. 3 is not something to fret about. Over a long run it may make a difference but day to day I don't see an issue. I will record the variation along with the meter reading to see what kind of difference it will make over a longer period. I will begin using the new meter for my 1hr and 2hr readings when figuring out what foods do what to me. The original meter is the one I will use for the Dr's required tests.

I haven't tested my MIL's One Touch Ultra 2 meter. Once I do that I will post it comparing it to the Verio's readings.

 

[smorgan]

OK. Got my new meter with control solution today. So I did the testing described earlier in this thread. Here are the results:

Test Solution is the Mid-Level (Level 3) from One Touch.

Original Meter - One Touch Verio
Test Strip Range 102-138. (Median 120) Lot # 4014397
Test 1 - 123
Test 2 - 125
Test 3 - 121
Test Average - 123
Meter Variation from Median - 3

New Meter - One Touch Verio
Test Strip Range 102-138. (Median 120) Lot # 3900006
Test 1 - 119
Test 2 - 118
Test 3 - 123
Test Average - 120
Meter Variation from Median - 0

Right now there is not a big variation in average readings. 3 is not something to fret about. Over a long run it may make a difference but day to day I don't see an issue. I will record the variation along with the meter reading to see what kind of difference it will make over a longer period. I will begin using the new meter for my 1hr and 2hr readings when figuring out what foods do what to me. The original meter is the one I will use for the Dr's required tests.

I haven't tested my MIL's One Touch Ultra 2 meter. Once I do that I will post it comparing it to the Verio's readings.

Those are really impressive numbers, kudos to the manufacturer. But, I do see a 3 point variation on the part of the strips. The meter appears to contribute no inaccuracy at all.

What might be interesting is to subtract 3 from all readings you take with these strips and this meter. Then, do the same calculations for the next batch of strips. If, over time and several batches of strips, the "corrected" numbers are more consistent than the measured ones, it will show that this type of correction is warranted and is one way to improve the accuracy of readings we take.

 

[Snorebaby]

Those are really impressive numbers, kudos to the manufacturer. But, I do see a 3 point variation on the part of the strips. The meter appears to contribute no inaccuracy at all.

What might be interesting is to subtract 3 from all readings you take with these strips and this meter. Then, do the same calculations for the next batch of strips. If, over time and several batches of strips, the "corrected" numbers are more consistent than the measured ones, it will show that this type of correction is warranted and is one way to improve the accuracy of readings we take.

I have went back and subtracted 3 from my previous readings as I was using the same lot # for them. It doesn't really make much of a difference in the overall, it is still only 3 and only a 1/10 of a point in my estimated A1c.

I just opened a new vial with a different lot # for my original meter. The tested strips are reading 8 points higher on average. I have now put that number in my spreadsheet going forward. I will see what that does to my overall and estimated A1c.

On a side note...my #'s are looking real good. I am averaging 124 for the past 14 days.:biggrin: I go to the Dr on the 22nd.

 

[Papa Diva]

Testing venous blood with a meter makes no sense. They have a built-in correction factor (calculation) to 'translate' from the capillary reading to what should be the venous reading. They are always different by a fairly predictable amount. In order to simplify things, all the meters built in this correction several decades ago in order to approximate a venous blood reading as closely as possible. So, if you test venous blood with a meter, the built-in correction is inappropriate and the result won't mean much.

I think that you are confusing venous blood results with plasma-based BG results. Venous blood is tested in the meters the same as capillary blood - it's a whole blood measurement. Nowadays lab BG is tested using plasma - the blood in the tube is spun to separate the blood cells. Plasma is tested as it is considered more accurate.

So venous blood versus capillary blood (are pretty much the same). I think venous blood is more accurate as it's not mixed with other body fluids (that can happen when squeezing it from your finger), and what's in your vein is more current than what's in your peripheral digit.

Yes, there is a difference between plasma BG readings and whole blood readings. Meters have a correction built-in to off-set the differences. So they read whole blood, but the results are returned as plasma-based numbers.

Here's an article from a few years ago when the were making the switch to plasma and the meters were being adjusted to uplift the meter numbers to match plasma results.

Plasma Glucose Meters and Whole Blood Meters | Joslin Diabetes Center

Until the last couple of years, all blood glucose (blood sugar) meters read the glucose level in your blood sample as whole blood. Then several years ago one manufacturer developed a meter calibrated to read the blood glucose sample as if it were plasma. Why? Because the results of blood samples taken from your vein at your doctor's office or lab are reported as plasma. By having the meter record results as plama glucose, you and your healthcare team can more easily compare your lab tests with your blood glucose meter results. Several other meter manufacturers subsequently followed suit, so that today most newer meters provide blood glucose (sugar) readings as plasma glucose readings.

What's the difference?" you might ask. The difference is that plasma numbers read about 10 - 12% higher than the older whole blood numbers. So if your fasting and pre-meal blood glucose target is 90 - 130 mg/dl plasma glucose, it would be 80 - 120 mg/dl if your meter reads whole blood.

So, it's important for you to know what your meter reads, and then what your targets are for the meter you are using. Check your instruction book, contact the manufacturer of your meter, or ask a diabetes educator to find out how your meter reads.

As of July, 2002, the Joslin Web site is listing target blood glucose levels on its Online Diabetes Library as plasma glucose levels to reflect this change. For individuals who use the Online Diabetes Library as a resource to refer to on a regular basis, this is the reason for slight changes in certain target levels presented in this material.


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[Papa Diva]

OK. Got my new meter with control solution today. So I did the testing described earlier in this thread. Here are the results:

Test Solution is the Mid-Level (Level 3) from One Touch.

Original Meter - One Touch Verio
Test Strip Range 102-138. (Median 120) Lot # 4014397
Test 1 - 123
Test 2 - 125
Test 3 - 121
Test Average - 123
Meter Variation from Median - 3

New Meter - One Touch Verio
Test Strip Range 102-138. (Median 120) Lot # 3900006
Test 1 - 119
Test 2 - 118
Test 3 - 123
Test Average - 120
Meter Variation from Median - 0

Right now there is not a big variation in average readings. 3 is not something to fret about. Over a long run it may make a difference but day to day I don't see an issue. I will record the variation along with the meter reading to see what kind of difference it will make over a longer period. I will begin using the new meter for my 1hr and 2hr readings when figuring out what foods do what to me. The original meter is the one I will use for the Dr's required tests.

I haven't tested my MIL's One Touch Ultra 2 meter. Once I do that I will post it comparing it to the Verio's readings.

Okay. I am not sure how to interpret this.

So what is your actual BG reading on the Verio and the ultra2? Taken at the same time?

I always see the Verio results significantly higher than the Ultra results (yet the control solution for both returns numbers in the range - mostly at the mid point). The Verio always reads anywhere between 20-50 points higher.

So test your blood (using the same drop of blood) on both meters and see what the results are, then do the control solution test.

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[Snorebaby]

Okay. I am not sure how to interpret this.

So what is your actual BG reading on the Verio and the ultra2? Taken at the same time?

I always see the Verio results significantly higher than the Ultra results (yet the control solution for both returns numbers in the range - mostly at the mid point). The Verio always reads anywhere between 20-50 points higher.

So test your blood (using the same drop of blood) on both meters and see what the results are, then do the control solution test.

.

To interpret the results of my post, using a consistent amount of glucose (control solution) you are actually testing the strips/meter combo and comparing them to the strip range of 102-138. I believe that is why One Touch advises to do a control test (1 strip) with every new vial to make sure it is within the range. I feel that if the lot # of the strips are the same, the results should be the same (averaging +/- 1 or 2 points).

The reading should fall in between those variables and should be around the mid-point. IMO, if you do it 3 times you can average the amount the combo is above/below the median and adjust your readings accordingly, which over a period of time, will be more accurate to your actual BG amount.

If you notice, the readings are completely different for the meters and both meters are the same model. One is 3 points higher and the other is 0 points from the median #. Not much difference with the 2 lot #'s. But since then, I have opened a new vial of strips with a different lot # for the original meter and they read an average of 8 points higher from the median #. I adjust my reading to compensate for this.

I have only done the same drop of blood comparison test twice. The first time the Ultra2 read 117 and the Verio read 132, a difference of 15pts. The second time (about a week later) the Ultra2 read 115 and the Verio read 127, a 12pt difference.

I have not done the control solution test with the Ultra2 as my MIL is low on test strips and hasn't gone to get more as of today. As soon as that happens I will do the test and report it here.