February, 2003
© 2000, 2001  Scott S. Emerson, M.D., Ph.D.
Session 2: 122
Comparison of Parameterizations
ASSERTION: Interpretability of boundary scales
The formulation of error spending scales is not well understood by the researchers developing such methods
·Lan & DeMets (1983), Kim & DeMets (1987), Jennison & Turnbull (1989 and 2000) all describe error spending functions which mimic O’Brien-Fleming (1979) or Pocock (1977) group sequential designs
·In fact, for different levels of type I (or type II) error, the error spending functions are different within those families of designs