Not very much so, according to my own experience and my research on the net.
Mayo Clinic site lists a number of factors that can affect meter accuracy. Among them, test strip problems, monitor problems, improper coding, not enough blood applied to the strip, site location other than your fingertip, some substances on your skin and certain blood disorders, as well as some medications.
Test strips problem means that the strips were outdated or not stored properly. Monitor problems can mean weak batteries or the strip not fully inserted. Substances on one’s skin simply mean having to wash hands prior to sticking.
And last but not the least, Mayo Clinic suggests to match your reading with the lab results. However both have to be done at the same time. I likely will never resort to this as I don’t even check my blood sugar as often anymore.
Healthline site goes into even more detail by comparing home results with the ones done at the hospital, and explains the reason for the difference in a very technical manner. Basically it says that the hospital results are more accurate because BG checks are done by the trained technicians in a temperature- and humidity-controlled environment, using a much larger blood sample and calibrating BG machines several times a day.
All this is apparently hearsay and was written by someone who has never actually worked on a hospital floor. I can tell from my firsthand experience, that AccuChek machines we used on the floor were not calibrated “several times a day”. In fact, only when a certain machine started showing strange results, was it sent downstairs to the lab for re-calibration. But not on a daily basis, I can assure you of that.
Controlled environment consisted of a heater and air conditioner unit by the window which could be turned up or down as the patients see fit. Not done automatically by any means.
Now on to the “trained technicians”. My personal training was done on the job and has lasted a few minutes. I was simply shown how to do it and then I was on my own.
All this in a local hospital that is a part of the Cleveland Clinic system, no less.
Here now, I’ve googled down the lancets that we were using on the floor. They were easy to use: turn & pull out the bottom blue tail, place the lancet onto the fingertip, press the top blue button, and voila.
Still love them but will be using my pen.
Bottom line, blood glucose meters aren’t a math science and the results will always vary for a number of reasons. This is the way it is now and will likely continue indefinitely so why not live with it.
All the above represents my two cents.