Abstract

Of the three mainly used non-invasive modalities for the accurate measurement of subjects’ systolic and diastolic blood pressure, the mercury sphygmomanometer is the most widely accepted and used. However due to concerns of toxicity in the usage and disposal of mercury, several countries have directed policies to minimize the use of mercury instruments. The digital sphygmomanometer is also widely used since it is relatively cheaper, non-toxic and does not require auscultation skills to obtain blood pressure readings. However the concern is the accuracy and validity in the values obtained for systolic and diastolic blood pressure using the digital/automated sphygmomanometer. This study is posed on the evaluation of the validity and accuracy in comparison between mercury sphygmomanometer and the digital sphygmomanometer. Fifty (50) subjects were selected using the simple random sampling techniques from among male and female above 18 years old that complied with all instructions and met the inclusion criteria for this study. The study samples used were recruited on notice and home visits by taking blood pressure measurement using left and right arm. Findings from this study implied that there is a significant difference in the systolic blood pressure values obtained using the manual sphygmomanometer and the digital sphygmomanometer in the left arm (p=0.005) and in the right arm also (p=0.000). There is no difference however in the diastolic blood pressure values obtained using the manual sphygmomanometer and the digital sphygmomanometer in the left arm (p=0.174) and in the right arm (p=0.226). Findings from this study also showed a non-significant inter-arm difference (IAD) between systolic blood pressure using manual sphygmomanometer (0.34±1.22) and using digital sphygmomanometer (0.35±1.28). Likewise there is a non-significant inter-arm difference (IAD) between diastolic pressure using manual sphygmomanometer (2.43±1.60) and using digital sphygmomanometer (2.07±1.27). Based on the findings of this study it was concluded that the digital sphygmomanometer is reliable in terms of measuring systolic blood pressure, but in measuring lower blood pressures care must be taken in the use of digital sphygmomanometers.