Primary outcome
BLOOD
The primary outcome measures were systolic and diastolic blood pressure, measured using a calibrated Omron Premium Blood Pressure Monitor Device, Omron HEM-7322. which is reported to produce digital and accurate reading utilising the dual check calibration system. We measured blood pressure twice from the right arm with the person sitting upright. We took the second measure after at least 5 minutes of rest from the first measure and used the average of the two measures. A third measure was taken if the difference between the first two measures was more than 20%, otherwise we took the average of the closest two readings To check the accuracy of the readings, we measured blood pressure from 10 adults using both Omron HEM-7322 and a standard analogue device to compare. Our data showed that the Omron HEM-7322 over-estimated SBP on an average by only 6% (standard deviation (SD) 8%) and DBP by 3% (SD 5%). Given the variation was less than 10% between two devices, we used our data measured by Omron HEM-7322 without further adjustment for overestimate.