Is there a difference in accuracy between having blood pressure taken by a professional and a machine?

Possibly: It is important to be certain that the blood pressure is accurately taken. If a patient is checking his or her own blood pressure, i commonly will have that patient bring the machine in so that i can compare the readings to make sure that the home blood pressures are accurate. Sometimes they are and sometimes they are not.

It depends: Usually a person is more accurate than the machine, especially if no one is paid to check the machine as it ages.