February, 2003
© 2000, 2001  Scott S. Emerson, M.D., Ph.D.
Session 2: 3
Need for Monitoring a Trial    
Fixed sample two-sided tests
Test of a two-sided alternative (q+ > q0  > q- )
·Upper Alternative:    H+: q ³ q+     (superiority)   
·Null:                          H0: q = q0       (equivalence)
·Lower Alternative:    H -: q £ q-       (inferiority)
Data analyzed once at the end of all data accrual
Decisions:
·Reject H0 , H -   (for H+)   ÜŞ       T ³ cU 
·Reject H+ , H -   (for H0)   ÜŞ   cL £ T £  cU 
·Reject H+ , H0    (for H -)   ÜŞ       T £  cL