Skip to main content

Table 2 Allocation ratios, overall power and sample size comparisons for the adding a treatment arm design using optimal allocation when treatments finish recruitment at different times

From: Designs for adding a treatment arm to an ongoing clinical trial

Stage 3 ratioStage 2 ration23CorrelationOverall power
1:0.22.015:1:11000.1700.852
1:0.31.932:1:1930.1760.850
1:0.41.856:1:1850.1810.848
1:0.51.791:1:1780.1860.847
1:0.61.730:1:1710.1910.845
1:0.71.678:1:1640.1970.844
1:0.81.632:1:1580.2020.843
  1. The total sample size of the trial is based on an adding a treatment arm with 1:1:1 allocation design with a marginal power of 90% and an FWER of 2.5%