title: Using Hawksley random zero sphygmomanometer as a gold standard may result in misleading conclusions.
abstract: We combined a database of paired blood pressure measurements taken using the Hawksley random-zero sphygmonanometer and a standard mercury sphygmomanometer and a database of paired measurements made on a SpaceLabs 90202 ambulatory blood pressure recorder and standard sphygmomanometer to determine how the SpaceLabs 90202 would have fared if it had been assessed against the Hawksley random-zero sphygmomanometer instead of a standard sphygmomanometer. The pooled database contained 255 triplicate readings. Using the standard sphygmomanometer as gold standard, the Spacelabs had a median error of 2 mm/Hg for both systolic and diastolic. Against the Hawksley random-zero sphygmomanometer, median error was -3 mm systolic and -6 mm diastolic. The proportion of errors > 10 mm rose from 11% (systolic) and 9% (diastolic) with the standard sphygmomanometer to 16% and 29% with the Hawksley random-zero sphygmomanometer. Because it underestimates systolic and diastolic pressures, the use of the Hawksley random-zero sphygmomanometer as a gold standard may have resulted in misleading conclusions about performance of some automated BP recorders.
authors.affiliation: Department of Epidemiology & Preventive Medicine, Royal College of Surgeons in Ireland, Dublin.
authors.forename: R M
authors.initials: RM
authors.lastname: Conroy
authors.forename: N
authors.initials: N
authors.lastname: Atkins
authors.forename: F
authors.initials: F
authors.lastname: Mee
authors.forename: E
authors.initials: E
authors.lastname: O'Brien
authors.forename: K
authors.initials: K
authors.lastname: O'Malley
mesh_terms: D000328:Adult; D000337:Aerospace Medicine / Q000295:instrumentation; D000368:Aged; D016477:Artifacts; D001795:Blood Pressure Determination / Q000295:instrumentation*; D016208:Databases, Factual; D006801:Humans; D006973:Hypertension / Q000175:diagnosis; D008875:Middle Aged; D018670:Monitoring, Ambulatory; D011897:Random Allocation; D012015:Reference Standards; D015203:Reproducibility of Results