February, 2003
© 2000, 2001 Scott S. Emerson, M.D., Ph.D.
Previously
described methods for implementing stopping rules
·(Adhere
exactly to monitoring plan)
·(Approximations
based on design parameters: Emerson and Fleming, 1989)
·Christmas
tree approximation for triangular tests: Whitehead and Stratton,
1983
·Error
spending functions: Lan and DeMets, 1983; Pampallona, Tsiatis, and
Kim, 1995
·Constrained
boundaries in unified design family: Emerson, 2000