Sequential equivalence testing and repeated confidence intervals, with applications to normal and binary responses

C. Jennison, B. W. Turnbull

Research output: Contribution to journalArticlepeer-review


We propose group sequential tests of the equivalence of two treatments based on ideas related to repeated confidence intervals. These tests adapt readily to unpredictable group sizes, to the possibility of continuing even though a boundary has been crossed, and to nonnormal observations. In comparing two binomial distributions, the required sample size depends strongly on the average success probability and an adaptive choice of group size is needed to produce an efficient test meeting specified error probability constraints. A special case is the experiment where interim analyses are performed, not for the purpose of early termination but simply to adjust the sample size so that nominal error rates will be guaranteed, despite the presence of a nuisance parameter.

Original languageEnglish
Pages (from-to)31-43
Number of pages13
Issue number1
Publication statusPublished - 1 Mar 1993


  • Adaptive procedure
  • Clinical trials
  • Confidence intervals
  • Equivalence
  • Group sequential methods
  • Interim analyses
  • Repeated confidence intervals
  • Stopping rules

ASJC Scopus subject areas

  • Statistics and Probability
  • Biochemistry, Genetics and Molecular Biology(all)
  • Immunology and Microbiology(all)
  • Agricultural and Biological Sciences(all)
  • Applied Mathematics

Cite this