Home A1C kits

I have read some seriously mixed reviews on the home A1C kits… some say they are extremely accurate others say there very inaccurate… Anyone here have experience using one? Ever compared it to a lab result? I actually read a review on amazon were the women read an article that these machines can read up to 11% lower than actual lab results. Any thoughts… opinions… :slight_smile:

My personal opinion after having used 3 of them. Don’t waste your money. If you have good medical insurance, the lab tests can be free, like with my Medicare/supplemental insurance. I pay nothing for labs, doc visits, hospitalization, pump/sensor supplies.

I found that the home A1c kit results were not at all accurate.

My husband used a couple (4 tests total) to figure out how he was doing when he was originally trying to lower his A1C. It did give him an idea. But he wasn’t looking for accuracy.

He got the most benefit from using my Libres off and on. It was easy to get extra of those because at the time insurance wasn’t covering them anyway.

A1C can vary 1/2% up or down just depending on lab, their equipment and protocol which is why for patients on a CGM, doctors more and more are no longer looking at A1C. For those of us on Dexcom, GMI (Glucose Management Index) is the best measurement as we are all being compared on the same basis. Sort of like we are all going to the same (Dexcom) lab with the same equipment for our results. Not all labs are even certified so their A1C results are suspect at best, although they are good to get a baseline and a number to work at improving as long as they keep using the same lab.


I have used home test and compared them to lab test. Home test were consistently 1.2 lower than lab. 5.9 versus 4.7

So I can use them to see how things are going. I am on medicare advantage and allowed one A1c each three months.

My Dexcom Clarity estimated A1C has been exactly the same as I’ve received from the lab over the past 12 months (4 different results).

I know for others, Clarity’s estimated A1C can be off by 10% or more.

I think you could make an argument that the Clarity GMI is consistenntly measured in the same way with the same algorithms and that patients that are off from their lab report, the issue is with the lab rather than Dexcom. Labs have a stated ±1/2 % tolerance but many labs are not certified and therefore their results can be even farther off.

Take your 90 day average and do this

(46.7+YOUR 90 DAY AVERAGE)/28.7

Very close it will be

example 46.7+137=183.7

183.7 divided by 28.7 equals 6.4


(46.7+YOUR 90 DAY AVERAGE)/28.7

Where did you find this equation? My daughters A1C with this equation is 5.4, the machine told us 4.2 which I found difficult to believe, her glucose is never below 95 ( unless having a hypoglycemic situation) I think this equation is much more accurate

I found it here - I just used 90 day average because of blood work intervals being normally 90 days


I reverse engineered the math or found it somewhere else - I forget

I posted it because I have seen it close to my wife’s bloodwork


My Clarity estimate has always been around 15% lower than my lab result. I always go to the same lab, which is in the big-city hospital where my endo is, and it also does the tests for ER and ICU. I’m going to trust the hospital lab over Dexcom’s algorithm.

That is fine as long as when you are comparing A1C’s with other patients, those patients got their A1C at the same hospital you are using. Otherwise the comparison is near useless as whom you are comparing to may have been done on different equipment with a different protocol and can be off by as much as 1% as that is the current tolerance among certified labs. That is why Dexcom does not give you an A1C. They give you a GMI as that puts all the Dexcom users on the same algorithm.

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My endo’s office tests A1C with an in clinic test that uses blood from and finger stick. The result was within 0.3% of lab tests from two different labs taken about 3 months before and after. Clarity’s estimate about 1% higher than lab and clinic tests.