The way I know is I test them on an 0.05% dextrose solution but I won't get into the complications. Just buy a cheap one and know that it will read a little high. There would be the consideration that it might tell you that you are not in a hypo when in fact you are but if you are a T2 you are unlikely to hypo. Just find out what spikes you and fix it.Thanks, sounds complex......how do I know which way it is inaccurate? wouldn't I need an accurate one to test it against?