## A place to start? [Two-Stage / GS Designs]

Dear ElMaestro,

❝ can you run a series of sims where you include "20 more subjects than necessary" in stage 2 where a stage 2 is called for?

that could indeed be done within the (in)famous package Power2Stage, function power.2stage.fC() using the argument n2.min. At least partially because n2.min assures a minimum sample size for stage 2, if stage 2 is called for and the estimated sample size is smaller than n2.min.

But that's not the problem Helmut has described, at least as I understand it. Here we initiate a stage 2 from the perspective of the AUC evaluation where it is not neccessary to initiate one.

If having more than necessary number of subjects is a problem at all? My gut feeling says no.

Regards,

Detlew