The aneroid and wrist measures did not significantly differ from mercury measures at any age.
For those less than 21, the aneroid monitor was significantly lower than the mercury measurement (P = .086, Cohen's d =.34, a small effect) and the arm measurement was significantly greater than the mercury for those 21 to 24.5 (d = .60, a medium effect).
The variability of the differences between these measurements and the mercury was highest for participants over age 50, with the exception of the aneroid. Further, the variability of the difference between wrist and mercury measures was significantly higher than other monitors for participants over age 50.
With regard to diastolic pressure, the wrist measure would be graded lower than C, but the arm and aneroid measures would receive B grades.
This study and others demonstrate the inaccuracy of automated BP monitors and traditional aneroid manometers when compared to the gold standard mercury column manometer, especially for different age groups.
It is also essential to recognize the need for frequent calibration of aneroid units with the mercury column manometer.
As in other studies and reports, (7,9,12,15) our study found that the automated arm and wrist units and the aneroid sphygmomanometer used in the study did not pass standards set forth by the BHS and AAMI due to variability of systolic and diastolic BPs in mmHg when compared to the control.
Calibrate BP manometers (aneroid and automatic) twice each year against a mercury manometer, and/or return to manufacturer for calibration and repair.