The %FactorialPowerPlan macro can be used to do sample size and power calculations for planning either a factorial or fractional factorial experiment. The calculations can be done for either posttest-only or pretest-posttest designs. Participants can either be assumed to be independent, or nested within existing clusters as discussed in Dziak, Nahum-Shani, and Collins (2012).
The macro can be used for three separate purposes:
- to calculate statistical power based on an available sample size and assumed effect size,
- to calculate required sample size based on a desired statistical power and an assumed effect size, or
- to calculate minimum detectable effect size based on available sample size and desired statistical power.
FactorialPowerPlan (Version 1.0) [Software]. (2013). University Park: The Methodology Center, Penn State. Retrieved from http://methodology.psu.edu
Dziak, J. J., Collins, L. M. & Wagner, A. T. (2013). FactorialPowerPlan users' guide (Version 1.0). University Park: The Methodology Center, Penn State. Retrieved from http://methodology.psu.edu