Does anyone know if the home A1C blood test kit are accurate?
I’ve heard the Bayer test recommended as accurate.
The home A1C test quits have the same level of accuracy as a lab.
I agree. Pretty close to lab testing.
I'm pretty sure my doctor uses bayer in his clinic each visit. The results I get there match the relion (walmart) kits I've used at home.
The National Glycohemoglobin Standardization Program (NGSP) was started to calibrate A1cs against a reference so that we have consistency across labs as well as report independently on the accuracy of different test methods/tools. The latest survey results show that the Bayer A1c Now still has pretty poor performance, having as much as an average error of 0.42%.
Another recent study of so-called point of care systems (such as those used in doctors offices), including the Bayer A1c Now also found that they didn't have very good accuracy. The Bayer A1c Now performed so poorly, a complete evaluation using all the protocols was not performed. On the other hand, David Mendosa looked into the Relion A1c available quite affordably at Walmart and had very good things to say about Heritage the lab used (you have to mail off the test). Heritiage/Apprise uses the Roche Cobas Integra 800 CTS one of the best performing methods out there, assessed by the NGSP as having a maximum error of 0.11% and low variability.
My conclusion, if need to depend on the home A1c test then the Relion is the best choice right now.
Not to get pick, Brian. But unless my math is faulty a .42% error rate is a 99.58 success rate! That sounds pretty ok to me!
It's kinda of confusing what the .46% for the A1C Now means.
Looking at the chart from the link, if the NGSP reference value is 5.6, a Bayer A1C Now would give you an average of 5.14 from 28 different labs. If the NGSP reference value is 9.4 then the A1C Now average from the 28 labs was 8.49. An NGSP reference value of 7.2 would give an average reading of 6.59 from the 28 labs using an A1C Now kit.
Whatever it means, like Brian says, an A1C Now kit didn't give a very accurate reading across a range of reference A1Cs and generally the A1C Now underestimates the A1C.
Shawnmarie is correct I was quoting an absolute error. But it turns out I quoted wrong and it is even worse: The test had each lab (there were 28 labs) do three measurements and computed the average absolute error. Here is the date:
Actual A1c Measured A1c Error
5.6 5.14 -0.46
9.4 8.49 -0.91
7.2 6.59 -0.61
I read the wrong line. In fact they found the Bayer A1c was off by nearly 1% at times. That is a relative error rate of nearly 10%. That is almost as bad as a glucose meter. That is really bad.
Yeah, no doubt, and I think if you are interested in A1C trends, as long as the A1C Now error is consistent, you can get a good idea what's happeing from month to month by keeping tabs on your A1C using the home kit.
FWIW, when CVS was doing their free A1C screening offer, they were using the A1C Now kit. They had me at 5.4 when my offical lab reading was actually 5.8. That seems within the range the study posted by Brian had.
Ah, that is different, and all good points. I also wonder what the error rate is for the lab test? I assume the "actual A1C" means lab tested A1C. I believe the reason I thought pretty positively about the home test is because the lab results also had an error rate and so the difference was smaller.
Wow - another awesome TD discussion.
I measure mine at home once a month. I've always used the Bayer and think they're pretty accurate, and I agree that they are more useful in spotting trends over a few months. And since I test 6x per day, I've gotten pretty close to guestimating where I'll be.
However, the price on the Bayer has recently skyrocketed. I used to pay $29 for 2 at Target, and now the price is $34. At CVS it is $36, and at Walgreens $42.
I never thought about WalMart since I'd have to travel a bit to get to one, but next time I'm in the neighborhood will check them out.
Holy smokes - I just looked on the WalMart website and their cost for the Bayer 2 test kit is $47! Yikes.
The Relion kit is $8.98 for one test, but you have to send it away and then get results 5 days later, which I could live with.
I think I'm going to order a couple of them via online.
American Diabetes warehouse shows 36.99 for 2 test kit bayer a1cnow.
they claimm full retail is 49.99.
Must have been huge price hike recently as old price was 25 to 29 dollars.
I guess I am forewarned ( from experience ) ...Bayer test always lower than Lab test ...with averages: 6.9 Lab , 6.5 Bayer around similar time done at Lab . I have been able to get free Bayer A1C tests at Pharmacy and CDA's NAGM/Professional Conferences :)
I've used the relion a few times. Its a good set, but it is quite difficult for me to get enough blood on the test area. I'd reccomend making sure your hands are warm, and stabbing your finger violently in order to be sure you get enough blood on the thing in one shot, it'd be a shame to waste one...
I test blood for a living.
The home kits are accurate if they are used correctly and consistently.
It is very difficult to compare different methods and expect the same result.
even comparing laboratory methods that are closely monitored for consistency can have a large variance.
The best thing to do is choose one and stick with it, You will see when you are moving up or down. If you switch methods you can easily lose track due to the variances.
And BTW the COBAS INTEGRA is a very old instrument and the accuracy is not terribly good. I was actually surprised to see someone mention it at all as I thought it was nearly retired.
The column method has been around a while and is always the most consistent.
It really hardly is worth comparing them though, as I said they are all pretty accurate, the lab methods and the home methods, if you are competent enough to use them correctly.
There are so many things that throw off the test anyway, like your sugar at the time of the test and how long the blood sits around before it is tested, and weather or not you are dehydrated. If you sugars run high at night it will significantly raise your a1c because red blood cells are produced mainly while we sleep.
I only use it as a guide. Weather you are a 6.5 or a 6.9 hardly matters unless you are moving from a 6.5 to a 6.9 and nothing is different for you,
I am curious though about why anyone would want to test at home. Usually the A1c test is covered by insurance when done at a lab, and it is much cheaper to run that way. Most Doctors don't even like to accept outside laboratory results, let lone one that the patient did at home.
I'd be curious to know how closely the A1C @ home folks are seeing the tests comparing to their BG averages? Mine tends to be a little bit off a lot of the time, which I figure is due to some sort of reporting error w/ the CGM or something like that. I haven't ever tried the at home tests as I figure if the test covers about 3 months and I get them 4x/ year, I should have the whole year covered. I use my CGM average and average BG to keep an eye on the "big picture" in between tests.
That's a good question. My last one, 5.7 was a bit lower than I intuitively expected and the average at the time, 125 would have made for 5.9.
Thanks for your educated response, Timothy. Just fyi I test at home mainly because the "spirit moves me" and I want to know what it is and because I basically test for myself, not on demand. However, my latest doctor was not happy getting home results so I'll do my next one in the lab because I don't want to pay for both.
As for cost, I pay 20% for labwork (not sure how many of us are lucky enough to have full coverage!) which I don't remember, but think comes out to more than the $15 for 1/2 a test kit. Plus there's going to the doctor $20 copay though I usually will incorporate something else I need for the visit. But as I think about it, you know what the bottom line reason is why I prefer homekits? I resent like crazy having to fight to get the results for my own damn tests! Living in Guatemala for two years I was used to just walking into any lab, asking for whatever I wanted (assuming they knew what it was, couldn't get GAD when I wanted), paying about $15 and returning in two days for MYresults. Then if I wanted to bring them to the doctor to discuss, that was my choice. Kind of like an adult!