To obtain the values most representative of the patient s office blood pressure, evidence supports that at least two readings be taken on each of two occasions, at least one day apart. Blood pressure was measured by standard technique in all critical studies that have been used to develop recommendations for both the blood pressure levels at which to begin drug treatment as well as the blood pressure goals of treatment. Therefore, in order to make appropriate decisions in clinical practice, blood pressure should be measured with a properly calibrated and validated sphygmomanometer and with a standard technique similar to what has been used in studies.[36] Older studies used manual blood pressure determinations, such as with a mercury sphygmomanometer, while more recent studies have used fully automated oscillometric sphygmomanometers. A fully automated oscillometric manometer can be set to wait a specified rest time and take an average of several blood pressure readings with one activation. A semi-automated oscillometric device takes a single reading without a rest period after activation. SRs and meta-analyses have reported that blood pressure readings were similar when comparing fully automated oscillometric sphygmomanometer with daytime average ambulatory blood pressure readings, but routine office readings without standard technique averaged 7.0 to 14.5 mm Hg higher than fully automated readings.[37,38] In one SR, SBP readings using research quality manual or oscillometric technique averaged 7 mm Hg higher than fully automated oscillometric technique; however, in the one study included in the SR in which the order was randomized, there was very little difference between these two techniques, suggesting the others may have been biased by regression to the mean.