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When you go to the doctor's office, are they taking your blood pressure the right way?

If those steps aren't adhered to, there could be really substantial measurement and accuracy.

Studies have shown that you can overestimate your blood pressure by five to even 30 millimeters of mercury.

It's Tuesday, November 12th, and you're listening to Science Friday.

I'm Cyford producer Charles Berkwist.

You know, when I go to the doctor, each visit generally starts with me sitting up on the edge of a tall exam table, legs dangling in the air, arm held at a weird angle while an assistant straps on the blood pressure cuff. It turns out that's not right at all. And it turns out that little things being off when you're

having your blood pressure taken can make a big difference in the final numbers. Here's Ira Flato.

Joining me now to talk about this is Dr. Tammy Brady. She's medical director of the pediatric

hypertension program and professor of pediatrics at Johns Hopkins University in Baltimore.

She's one of the authors of a study on this topic recently published in the journal JAMA Internal

Medicine. Welcome to Science Friday. Thank you very much. You're very, very welcome. So I go to my

doctor's office. The assistant comes in to take my blood pressure. What do the guidelines say?

How should they be doing it?

Right.

So a lot of people don't recognize that there's a lot more complexity to measuring

blood pressure than just putting on a cuff and punishing a button.

There are a lot of very important preparatory steps

that need to be taken and a lot of important positions that we need to make sure that patients are in

in order to get the most accurate blood pressure. So the first thing that a person should do

before measuring their blood pressure is making sure that they have emptied their bladder,

make sure that they haven't recently eaten or had any nicotine or alcohol, because those things can all lead to an

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