I did this test 5 times, back to back on fast mode. Each time I got a VERY different reading, most normal but 2 abnormal. I took it on standard two times back to back and had normal, but widely different results. My husband took it once and it said his was abnormal, and took it again and it was fine. There are just too many variables for this to be accurate, and it alarmed me when I saw the abnormality detected.