Commonly used arm positions can overestimate blood pressure readings: study

There's definitely a huge variance in blood pressure readings depending on posture, relaxation, arm position, recent activity, etc. If you buy a blood pressure monitor, it's really interesting to see how "random" a single reading at the doctors' is, and how large your fluctuation throughout the day is.

That being said, it really makes me wonder about studies that correlate blood pressure with other things. Is the blood pressure really being measured "correctly" in all those studies? Or not?

In other words, if your "true correct" blood pressure is lower than what the doctor normally takes, but then a lot of the studies are based on real-life "incorrect" higher blood pressures, then don't you similarly want an "incorrect" higher reading for consistency? Or are the studies always really done with far more accurate blood pressure readings, where the patient sits still for 5 min beforehand, keeps their legs uncrossed, is totally free of stress and anxiety, didn't exercise beforehand, etc.?

Exactly, this is my concern as well. They say you have to be seated for 5 minutes at least, completely relaxed, not hungry, not having to go the bathroom, in a quiet a room, it must not be too hot or too cold, with both your feet on the ground, before you can have your blood pressure measured, otherwise the reading could be 'artificially' high. Really? It seems to me that if you do all these preparations, the reading will be artificially low, since such conditions are nothing like the conditions that you'll typically find yourself in through the day in your everyday life.

The goal is to get a clinically relevant measurement, captured at rest under specific conditions, not a measurement that's representative of a random moment during everyday life.