Answer: Several. The blood pressure measurements should be taken over time. Your doctor will want the individual blood pressures, but may also average them to get your “true” blood pressure. Use of a single blood pressure to determine whether blood pressure is controlled will yield a false result more than 20% of the time.
Take home thought: Between physician visits take your blood pressure at differing times of the day (most pharmacies have a self-starting blood pressure cuff), record all the blood pressures, and bring that list to your next office visit.