O'Brien Eoin; Petrie, James; Littler, William; de Swiet, Michael; Padfield, Paul L.; O'Malley, Kevin; Jamieson, Michael; Altman, Douglas; Bland, Martin; Atkins, NeilJournal of Hypertension: July 1990 Original papers: PDF Only Buy Abstract With the increasing manufacture of expensive systems for the measurement of ambulatory blood pressure there is a need for potential purchasers to be able to satisfy themselves that the systems have been evaluated according to agreed criteria. The British Hypertension Society has, therefore, drawn up a protocol of requirements for the evaluation of these devices. This protocol incorporates many features of the American National Standard for Non-Automated Sphygmomanometers but includes many additional features, such as strict criteria for observer training, interdevice variability testing before and after a month of ambulatory use, and a new system of analysis which permits the test system to be graded. It is recommended that manufacturers of ambulatory blood pressure measuring devices should obtain an unbiased evaluation according to a recognized standard before a device is marketed. © Lippincott-Raven Publishers.