Bests & Worsts Reviews from Amazon

I need to check my blood pressure frequently due to a health condition that can become much worse if it is not carefully regulated. I tried this BP monitor a number of times and checked it against one that has been compared favorably with that of my doctor. It consistently showed a BP 10 to 20 points below the accurate number. This is completely unsatisfactory. I'm very sorry because it is so easy to use. Unfortunately I missed the return date so I'm stuck with it but I will never rely on it. Hopefully if you give it a try yours will be accurate.