The initial design of the study was to use a co-primary end point of change in LV mass and change in pulse wave velocity. A sample size of 350 patients was planned to give 90% power to detect a difference in PWV with a p value of 0.025 and >90% power to detect a change in LV mass. When it became evident that was not achievable within the funded time frame the study was re-designed using the single end point of change in LV mass. With a p value of 0.05 and a power of 85%, it was calculated that 63 patients per group would be required. The sample size was calculated at 150 patients allowing for a 15% rate of missing data. This allowed a smaller sample size which was achievable within the funded time frame.