February, 2003
© 2000, 2001, 2003 Scott S. Emerson, M.D., Ph.D.
Session 1- Overview: 72
Example
Sample size distribution for designs considered here
Fixed sample design requires 100 subjects no matter how effective (or harmful) the treatment is
O’Brien-Fleming stopping rule requires fewer subjects on average (worst case: about 84)
Pocock stopping rule requires even fewer subjects on average over a wide range of alternatives (worst case: about 62)