Abstract:
:The 'at least as good as' criterion, introduced by Laster and Johnson for a continuous response variate, is developed here for applications with dichotomous data. This approach is adaptive in nature, as the margin of non-inferiority is not taken as a fixed difference; it varies as a function of the positive control response. When the non-inferiority margin is referenced as a high fraction of the positive control response, the procedure is seen to be uniformly more efficient than the fixed margin approach, yielding smaller sample sizes when sizing non-inferiority trials under identically specified conditions. Extending this method to proportions is straightforward, but highlights special considerations in the design of non-inferiority trials versus superiority trials, including potential trade-offs in statistical efficiency and interpretability.
journal_name
Stat Medjournal_title
Statistics in medicineauthors
Laster LL,Johnson MF,Kotler MLdoi
10.1002/sim.2476subject
Has Abstractpub_date
2006-04-15 00:00:00pages
1115-30issue
7eissn
0277-6715issn
1097-0258journal_volume
25pub_type
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