Sample Size Determination for Two-Stage Equivalence Test

• Activity Number: 626
• Type: Contributed
• Date/Time: Thursday, August 5, 2010 : 8:30 AM to 10:20 AM
• Sponsor: Biopharmaceutical Section
• Author(s): Mi-Chia Ma*+ and Shang-Bo Ye
• Companies: National Cheng Kung University and National Cheng Kung University
• Keywords: two-stage design ; non-inferiority test ; equivalent test

Abstract

In clinical research, a two-stage design usually indicated that the best of several experimental treatments were selected at the first stage and confirmed whether it's better than the standard treatment at the second stage. This paper proposed a two-stage design for non-inferiority test or equivalent test. We select the best of several experimental treatments at the first stage and test whether it is not inferior to a standard treatment or is equivalent to a standard treatment at the second stage. The design allows early termination when the null hypothesis doesn't reject. By minimizing expected total sample size for fixed significance level and power, optimal sample size and cut-off parameters are obtained. Finally, a simulation study was conducted to compare the difference of sample size between traditional design and two-stage design for non-inferiority test or equivalent test.