Coag-Sense versus CoaguChek xs and labs

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It's been a few months since I updated to this thread.

I've been using the XS for most of my tests. It's slightly easier to use than the Coag-Sense, but my bigger issue was the difference between the results in the two meters, and the Coag-Sense's sometimes significantly lower results than from the lab.

On 10/14, I tested with an old and a 'newish $30 XS' and got similar results - my 'old' XS gave me a 3.8. The 'newish' one gave me 3.9 - in other words, they agreed with each other.

My Coag-Sense gave me a 2.7.

The next day, I went to a lab for a blood draw. I dropped the dose from 7.0 to 6.5, and it hadn't changed (as expected) two days later when I tested again.

I contacted Coagusense, Inc (the manufacturers of the Coag-Sense meter and strips) on Saturday night - 10/16 about the issues that I've had for about two years. I'll let you know if they respond to my message.

When I get results from the lab, I'll probably post them here.

If I hear back from Coagusense, I'll report that here.

My initial posting in this thread was about Coag-Sense results compared to lab results. Maybe some of you can share your experiences.

(And, yes, the transfer tubes from Coag-Sense and others are useful for transferring blood onto the CoaguChek test strips)
 
It's been a few months since I updated to this thread.

I've been using the XS for most of my tests. It's slightly easier to use than the Coag-Sense, but my bigger issue was the difference between the results in the two meters, and the Coag-Sense's sometimes significantly lower results than from the lab.

On 10/14, I tested with an old and a 'newish $30 XS' and got similar results - my 'old' XS gave me a 3.8. The 'newish' one gave me 3.9 - in other words, they agreed with each other.

My Coag-Sense gave me a 2.7.

The next day, I went to a lab for a blood draw. I dropped the dose from 7.0 to 6.5, and it hadn't changed (as expected) two days later when I tested again.

I contacted Coagusense, Inc (the manufacturers of the Coag-Sense meter and strips) on Saturday night - 10/16 about the issues that I've had for about two years. I'll let you know if they respond to my message.

When I get results from the lab, I'll probably post them here.

If I hear back from Coagusense, I'll report that here.

My initial posting in this thread was about Coag-Sense results compared to lab results. Maybe some of you can share your experiences.

(And, yes, the transfer tubes from Coag-Sense and others are useful for transferring blood onto the CoaguChek test strips)
Hi. I discovered that my Coagucheck XS corrates closer to Quest Labs than Lab Corps. I asked about this to Roche and they said it depends on the reagents they use. Go figure. It's supposed to be International so I ask my internist to use Quest when I check lab with machine just once a year on my physical. Good luck Sheena
 
Yet another update - 10/19/21

On 10/14, I tested my INR using two CoaguChek XS meters and my Coag-Sense. I followed the next day with a test at Labcorp.

The two XS results were 3.8 and 3.9 - these were done within minutes of each other.
My Coag-Sense said 2.7. Also, within minutes of the XS meters.

The next day, the lab result was 2.9. While this result was close to the Coag-Sense result, the XS results were WAY off.

I realize that the XS numbers vary more from lab values the higher the INR becomes, but this result was much higher than it should have been.

On May 6, Labcorp results were 3.6.
A few hours later, the Coag-Sense meter gave me a 3.4, while the XS reported 5.1.

Maybe whatever threw my results far off of lab results has resolved itself, or the XS values are just WAY TOO HIGH to trust.

(This afternoon - 10/19 - I tested on the Coag-Sense PT2 and the CoaguChek XS (the one I bought for $30) and got similarly disparate results: Coag-Sense - 2.3, CoaguChek XS - 3.5. Both results are sort of in range - I will check again, and maybe a few weeks from now, I'll get another blood draw.

I may return to the Coag-Sense as my primary meter, because of near agreement with the lab. (Now I may have to get some strips).

Now, I'm still unsure of which meter to trust, but I'll probably use the Coag-Sense a lot more often than the XS.

I'll test again today, because I reduced my warfarin dose based on the high results of the XS meters. My concern with the XS is the same one that I had years ago -- if I reduce my dosing based on an inaccurate 'high' INR, will the reduced dose put me below 2.0? (I doubt that it will, and the results when INRs are in the low 2s seem to converge). I don't think that I'll fully trust XS values above 3.3 or so.

I know that the advice is to find a meter and stick with it. I'm just not sure which one to trust (I've been trusting the XS for the past 5 months). Maybe I should bet on the dark horse, instead.
 
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I'm sure that the lab results may differ slightly (or they SHOULD differ slightly).

Last year, I had a LONG series of conversations with LabCorp execs. They assured me that they thoroughly test ANY reagents used for INR testing, at the time they arrive, and daily, to assure accuracy.

Quest probably does a similar validation test whenever a new reagent arrives.

The whole thing with reagents is that it involves a bit of guesswork to assign a good number to a particular reagent.

In either case, even lab reagent values involve a bit of educated guesswork.

My HMO only works with LabCorp, so I don't see a way to have the results validated by another lab.
 
The next day, the lab result was 2.9. While this result was close to the Coag-Sense result, the XS results were WAY off.
I believe that you have reported this in the past a few times, and (it has been a while, so if memory serves) there is perhaps something about your "bloods" that makes the XS report badly compared to other sources
 
I notice that my coag-sense meter receives software updates over my WiFi a few times after I got my machine 7 months ago. Makes me feel better that someone in the background is tweaking the machine. When I first got it , it was all over the map with inconsistent results. Much more predictable now. Spot on with roche machine in my office.
 
I believe that you have reported this in the past a few times, and (it has been a while, so if memory serves) there is perhaps something about your "bloods" that makes the XS report badly compared to other sources
My Coag-Sense meter correlates perfectly with my Health Plan's lab machine. However, the Health Plan has never changed either their machine nor their reagent. Thus, the perfect correlation has never changed. With Covid, my overall diet has been unchanged for two years and so it is unlikely that my blood composition has changed either. Since I have added some of the supplements from the FLCCC doctors' recommendations, my INR has shifted but has been relatively easy to bring back to the middle of my range.

(Note- the FLCCC doctors group was founded by a bunch of Intensive Care Medicine professors at various medical schools and being professorial types, are among the most published doctors in the country). They recommend the use of supplements that have been found by "small" research studies in foreign countries to produce significant improvement in outcomes with Covid Symptoms. They claim that they have seen the same improvement in their patients at their University related Intensive Care Units. Note also that they are biased in that they only see very sick patients and not just starting to get sick patients in the Intensive Care and Emergency Room units. They would necessarily have a different viewpoint then family practice internists who rarely see very sick Covid patients and usually see patients only beginning to get sick.)

Walk in His Peace,
Scribe With A Lancet
 
They would necessarily have a different viewpoint then family practice internists who rarely see very sick Covid patients and usually see patients only beginning to get sick.)

This last statement I can’t ignore. Covid is so prevalent they think that family Physians don’t see sick Covid patients is ridiculous. I shouldn’t be shocked at the overall perception of the public I guess. They don’t have a clue what I and my colleagues have treated at all levels of the pandemic. Dealing with the illness and trying to convince the public that vaccines are safe to hoards of people.

Got my frustration out.
 
I notice that my coag-sense meter receives software updates over my WiFi a few times after I got my machine 7 months ago. Makes me feel better that someone in the background is tweaking the machine. When I first got it , it was all over the map with inconsistent results. Much more predictable now. Spot on with roche machine in my office.

It'd make me nervous to receive software updates on a medical device that my life depends upon w/o receiving information as to what changes were made and why. Do they provide this information?
 
I believe that you have reported this in the past a few times, and (it has been a while, so if memory serves) there is perhaps something about your "bloods" that makes the XS report badly compared to other sources
Pellicle - I started this thread - 7 pages ago - comparing Coag-Sense with CoaguChek XS.

In the past, I was finding that my Coag-Sense fairly regularly reported INRs below the CoaguChek XS, and often considerably lower than the labs. At the same time, users of the Coag-Sense were reporting values that were close to lab values.

I wondered what it was about my blood that confused the Coag-Sense.

After many tests, with similar differences between the XS and the Coag-Sense, I decided to trust the XS more, and have been using it more often than I used the XS.

But now there's THIS - results of the Coag-Sense more closely matched lab results. I didn't expect this. While it's possible that the update of Coag-Sense firmware might have resulted in more accurate tests - I got the same result on one test before AND after the update. The updates may be more cosmetic than about how the test functions.

As far as blood factors influencing XS errors - I had a complete blood panel last week, and nothing was out of range. I will probably continue testing with both meters, and do lab tests more frequently, and see if any trend becomes obvious.
 
It'd make me nervous to receive software updates on a medical device that my life depends upon w/o receiving information as to what changes were made and why. Do they provide this information?
I am much LESS nervous having a meter regularly updated - often correcting cosmetics and functions more than they touch the actual test process. This meter is FDA approved - any major changes that may have ANY IMPACT on test results would have to be cleared by the FDA.

I would rather go with a meter that receives regular updates than I would with one that hasn't changed in a decade or more. BTW - the new Roche meters have the capability of being updated through the Bluetooth or WiFi (I'm not sure which) connection built into the meter.
 
Pellicle - I started this thread - 7 pages ago - comparing Coag-Sense with CoaguChek XS.
I know, and I also know about our previous conversations. What are you getting at by taking this line of argument?

I can't explain why you have consistently reported these differences. I can only put it down to what I said.

Do you have another explanation? Because clearly a great may people don't have such differences.
 
My wife has been self-testing weekly using same CoaguChek XS since 2018. Since that time, there has been 25 times she also had INR done at Quest lab for comparison reasons (time between finger stick for XS and vein draw from lab was usually, if not always, within same hour).

After comparing the 25 lab tests at Quest to the results from the XS:

- INR from lab was lower than results from the XS 24 out of 25 times, on average, .338 lower (i.e. so on average, if XS reported 3.0, the lab reported 2.7 - rounded up).
- Only 1 time did the INR match.
- The largest deviation was .7 lower at the lab.

Last month, my wife had her INR done (vein draw) at the local hospital twice and both times the results were identical to her XS.

Curious to know what the results from another lab like LabCorp look like.

Perhaps if folks start reporting their comparisons we might see a trend from lab-to-lab versus that of the self-test machines.
 
Perhaps if folks start reporting their comparisons we might see a trend from lab-to-lab versus that of the self-test machines.
I've reported mine many times, I have not experienced a difference between my coaguchek and a lab of greater than 0.4 INR points and most are within 0.2
Here are mine again, you'll note that after 2012 I became less interested in checking (and in Finland for a while I was unable to)

date
Coaguchek INR
Lab INR
14/12/2012​
3.2​
3.4​
17/12/2012​
2.7​
2.8​
21/12/2012​
2.8​
2.8​
28/12/2012​
2.5​
2.6​
21/06/2014​
2.3​
2.5​
31/01/2015​
3.0​
2.9​
3/08/2015​
2.4​
2.6​
6/02/2016​
3.0​
2.8​
8/11/2017​
2.7​
2.6​
20/04/2021​
2.3​
2.3​
 
I've reported mine many times, I have not experienced a difference between my coaguchek and a lab of greater than 0.4 INR points and most are within 0.2
Your comparisons show an insignificant difference as on average, your Coaguchek is lower by a minuscule .04 than your lab results. I don't see a difference greater than .2 in your comparisons.
 
Your comparisons show an insignificant difference as on average, your Coaguchek is lower by a minuscule .04 than your lab results. I don't see a difference greater than .2 in your comparisons.

yes, my worst ones aren't reported in that because they were during my "learning curve" time
 
Note- the FLCCC doctors group was founded by a bunch of Intensive Care Medicine professors at various medical schools and being professorial types, are among the most published doctors in the country).

I would take anything from this group, FLCCC with caution. They promote ivermectin as a miracle drug and do not encourage people to get vaccinated. Virtually every physician that treats Covid patients strongly encourages folks to get vaccinated. For a group of frontline doctors, ostensibly in the trenches fighting Covid, strange that they would not encourage vaccination. Instead go on and on about the wonders of ivermectin, which makes them extreme outliers in the medical community.

"Derived from a compound discovered in a soil microbe in Japan, ivermectin has been called a “miracle drug” and “the penicillin of COVID” by Pierre Kory, a critical care physician in Madison, Wis. Kory is president of the Front Line COVID-19 Critical Care Alliance (FLCCC), "

It has not been shown to be the "penicillin of Covid" nor a "miracle drug"

https://www.scientificamerican.com/...rmectin-for-covid-despite-a-lack-of-evidence/
Many believe that they are doing great harm, by catering to the anti-vaxx crowd and giving people the false hope that they don't need to get vaccinated, as they can just take this "miracle drug" if they get infected.
 
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Many believe that they are doing great harm, by catering to the anti-vaxx crowd and giving people the false hope that they don't need to get vaccinated, as they can just take this "miracle drug" if they get infected.
some even have an amount of sound evidence.

However let Darwin do his job I say. All us idiots getting vaccinated don't have a clue.
 
However let Darwin do his job I say. All us idiots getting vaccinated don't have a clue.

Speaking of this, did you know that Ivermectin can be used to treat the side effects from the vaccine? We would expect no less from a miracle drug.

From the FLCCC website:

"Can Ivermectin help reduce the severity of vaccine adverse reactions?
Yes. If someone is suffering from a post vaccine syndrome, FLCCC clinicians and a growing network of colleagues have reported significant clinical responses to ivermectin. Please refer to our I-RECOVER protocol for further information."

Might want to pick up some ivermectin from your local vet and apply generously to that horn that sprouted from your forehead since taking the vaccine. I've been using it on my new ear that sprung up and I think it is helping. Does it look smaller to you?

1634878220082.png
 

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