Skip to main content

Table 2 Stopping boundaries in the MIRACLE trial

From: Treatment of Middle East respiratory syndrome with a combination of lopinavir/ritonavir and interferon-β1b (MIRACLE trial): statistical analysis plan for a recursive two-stage group sequential randomized controlled trial

BoundaryValueDecision
Efficacy sopping boundary (α1)0No stopping for efficacy
Futility stopping boundary (β1)0.2Stop the trial for futility if less than stage-wise P-value
Efficacy stopping boundary (α2)0.2250Stop trial for efficacy at the second stage or recalculate based on conditional power at first interim analysis
  1. α1 is the maximum probability threshold under which the trial will be terminated early for efficacy. β1 is the maximum probability threshold above which the trial will be terminated for futility. α2 is the maximum probability threshold (the sum of the stage-wise p-values), above which the study will be declared as met its endpoint