Effect of back support and stethoscope head on seated blood pressure determinations.

Seated BP measurements were taken in 48 men with a history of essential hypertension: in a chair with back support v on an examining table with no back support, and with bell v diaphragm stethoscope head in each condition. There were no significant differences between bell and diaphragm in SBP or DBP determinations. SBP was not significantly different between table and chair, but table DBP was 6.5 mm Hg higher (P less than .0001) than chair DBP. We conclude that back support, but not bell v diaphragm stethoscope head, affects seated BP determinations.