Conditional power with Fisher's least significant difference procedure

Abstract

Conditional power calculations are very useful for assessing the likelihood of an ultimately statistically significant result given the current data We show how to calculate conditional power in a multi-armed trial using the classic Fisher least sigmhnt difference, LSD, procedure. We obtain upper bounds on the probabilities of Type 1 and Type 2 errors analogous to those in two-armed trials, and show that these bounds are equalities under continuous monitoring.