Blood-pressure monitoring at home

* Check the packaging to make sure the monitor has been tested and validated for accuracy and reliability by the Assn. for the Advancement of Medical Instrumentation or the British Hypertension Society. Many monitors on the market are not -- and their readings may not be reliable. A list of validated monitors is available on the British Hypertension Society's website at www.bhsoc.org.

* White advises against more expensive monitors that can store readings. "The problem is the dates are not recorded, so it doesn't really help us figure out when readings fluctuated," he says. "I'd rather patients keep a flow sheet and have them mark the date, the time, the values and whether they did or did not take medications that day."

* Remember that the target rate for a home blood-pressure reading is lower than the target reading in a medical setting. Most physicians consider a patient with an office reading of less than 140/90 millimeters of mercury (mmHg) to be adequately controlled (or less than 130/80 if the patient has heart disease or diabetes).

"When patients come in and say 'I thought it looked pretty good -- meaning a reading of 138/88 -- that sounds good if it was in the doctor's office,' " White says. "It's not really normal, and it means that there's a very large chance that their pressure is not well controlled." For home-monitor readings, the target goal for treatment is under 135/85 and even less (130/80) in high-risk patients.

* Take the monitor to the doctor's office to be trained in its proper use and have a medical professional check to make sure the monitor is giving accurate readings.

* Change the batteries according to package instructions -- or if readings seem doubtful. "Some of these devices have a low-battery indicator that doesn't come on unless the batteries are totally depleted," White says. "If they are getting strange or unusual readings that do not make any sense, put fresh batteries in and see if that corrects the problem."