Sample Size Estimation Based on previous studies on exercise in hypertension, we expected the intervention to result in a decrease of daytime systolic 24-hour ABP (primary end point) of 6 mm Hg in the training group with no changes in the control group.
This difference was considered to be clinically relevant.
A sample size of 23 in each group has 80% power to detect this difference assuming that the common SD is 7 mm Hg with a 2-sided P 0.05.
We estimated the dropout rate to be 5% to 10%, leading to an overall sample size of 50 patients.