Agreement of Automated Oscillometric Blood Pressure Measurement Device with the Manual Mercury Sphygmomanometer

The usage of the manual mercury sphygmomanometer to measure blood pressure (BP) is universally regarded as the gold standard, but its use has decreased globally due to concerns about potential mercury toxicity. Automated BP devices have become more popular, though their accuracy in detecting hypertension hasn't been studied extensively. This cross-sectional study was conducted on 301 adult female students of the University of Delhi with the aim to assess the degree of agreement between standard manual mercury sphygmomanometer and automated BP monitor (Omron JPN1). Three consecutive BP readings were taken on the left arm by a certified medical doctor using both instruments. Bland Altman plots were created to assess the degree of agreement between the two BP devices and to test the accuracy of automated BP monitor in detecting hypertensive adults. The automated BP monitor underestimated the systolic BP measurement by 4 mmHg and diastolic BP measurement by 7 mmHg as determined by Bland Altman plot. Based on international validation protocols, a mean difference of < 5 ± 8 mmHg was established to assess the level of agreement between the two devices. The automatic BP monitor did not show complete agreement with the "gold standard" mercury sphygmomanometer. With growing restrictions on the use of mercury sphygmomanometers, its replacement with an equivalent mercury-free validated device is urgently needed.