Power
Sample size per group
Sample size in group 2
Allocation ratio n1:n2 :
Drop-out rate
Calculate
Press the Calculate button to calculate the sample size.
Calculate Sample size Power (output decimal places: )
Advanced Unequal sample sizes Account for drop-outs Bonferroni correction
Mean difference
Standard deviation 1
Standard deviation 2
Correlation
Standard deviation of differences
Specific options Use per-group standard deviations and correlation between groups to calculate the standard deviation of the differences