The goals of the factorial2x2 package are twofold: First, to provide
power calculations for a two-by-two factorial design in which the
effects of the two factors may be sub-additive. Power is provided for
the overall effect test for as well as the multiple testing procedures
described in Leifer, Troendle, Kolecki, and Follmann (2020). Second, to
analyze two-by-two factorial trial data which may include baseline
adjustment covariates. Further details are described in the factorial2x2
vignette.