Flexible stopping boundaries when changing primary endpoints after unblinded interim analyses.

@article{Chen2014FlexibleSB,
  title={Flexible stopping boundaries when changing primary endpoints after unblinded interim analyses.},
  author={L. M. Chen and Joseph G. Ibrahim and Haitao Chu},
  journal={Journal of biopharmaceutical statistics},
  year={2014},
  volume={24 4},
  pages={817-33}
}
It has been widely recognized that interim analyses of accumulating data in a clinical trial can inflate type I error. Different methods, from group sequential boundaries to flexible alpha spending functions, have been developed to control the overall type I error at prespecified level. These methods mainly apply to testing the same endpoint in multiple… CONTINUE READING