Depends on what you mean by a “true reading.” Were they done at the same time by using the same drop of blood? Human glucometers are required to be accurate to within +/-20% of a lab test reading of human blood, and AlphaTrak meters are presumed to meet the same standard for feline blood. When using a human meter for feline blood, this could be off a bit more from the lab test reading.
In a nutshell, because cat blood cells are smaller than human ones, the rate at which the blood is drawn up by the test strip is different, affecting the numerical reading. I’m probably not describing that very well, but it’s how I think of it. This means that, as a general rule, human meters will give a lower reading than the AlphaTrak for feline blood.
We briefly tested with two meters (AlphaTrak and Contour) just to see how they compared. The AlphaTrak usually, but not always, gave a higher reading. Even using two identical meters can give different readings though. (Remember the +/- 20% range.)