Statistical Methods in Non-Inferiority Trials - A Focus on US FDA Guidelines -

Kang, Seung-Ho;Wang, So-Young

  • Received : 2012.04.26
  • Accepted : 2012.06.18
  • Published : 2012.08.31


The effect of a new treatment is proven through the comparison of a new treatment with placebo; however, the number of parent non-inferiority trials tends to grow proportionally to the number of active controls. In a non-inferiority trial a new treatment is approved by proof that the new treatment is not inferior to an active control; however, both additional assumptions and historical trials are needed to show (through the comparison of the new treatment with the active control in a non-inferiority trial) that the new treatment is more efficacious than a putative placebo. The two different methods of using the historical data: frequentist principle method and meta-analytic method. This paper discusses the statistical methods and different Type I error rates obtained through the different methods employed.


Assay sensitivity;constancy assumption;Type I error


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Supported by : National Research Foundation of Korea(NRF)