The contribution of a routine maintenance regimen in assuring accuracy of aneroid sphygmomanometers is suggested by better performance of the inpatient devices compared to the outpatient devices.

During calibration, all 60 comparisons between the aneroid and mercury sphygmomanometers were within 3 mm Hg both at sea level and at high altitude.

Accuracy of only mercury and aneroid sphygmomanometers was tested and the results are shown in Table 1. Electronic sphygmomanometers were not tested.