These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: On the three-arm non-inferiority trial including a placebo with a prespecified margin.
    Author: Hida E, Tango T.
    Journal: Stat Med; 2011 Feb 10; 30(3):224-31. PubMed ID: 21213340.
    Abstract:
    Three-arm trials including the experimental treatment, an active reference treatment and a placebo are recommended in the guidelines of the ICH and EMEA/CPMP as a useful approach to the assessment of assay sensitivity. Generally, the acceptable non-inferiority margin Δ has been defined as the maximum clinically irrelevant difference between treatments in many two-arm non-inferiority trials. However, many recent articles discussing three-arm trials have considered a design with unknown Δ which is the prespecified fraction f of unknown effect size of the reference drug, where the prespecified fraction f is treated as if it were a revised margin. Therefore, these methods cannot be applied to the case where the acceptable non-inferiority margin must be a prespecified difference between treatments. In this paper, we propose a statistical test procedure for three-arm non-inferiority trials with the margin Δ defined as a prespecified difference between treatments under the situation that the primary endpoints are normally distributed with a common, but unknown, variance. In addition, we derive the optimal allocation that minimizes the total sample size. The proposed method is illustrated with data on a randomized controlled trial on major depressive disorder.
    [Abstract] [Full Text] [Related] [New Search]