Sample size
The primary endpoint in the present study was the paired
difference in small artery elasticity (SAEI) within each
group. With a sample size of n = 33 in each group, the
present study was designed to have not less than 80%
power to detect a true, within group difference of at least
1.2 ± 2 mL/mm Hg × 100 in SAEI in each of the two treatment
groups assuming a two-tailed alpha of 0.025 (preserving
to overall study alpha at 0.05).