February, 2003
© 2000, 2001 Scott S. Emerson, M.D., Ph.D.
Session 3: 21
Estimation of Statistical Information
Sample size
formulas used in group sequential test design
· n is the maximal number of sampling
units
· d1 is the alternative for which a standardized form
of a level a
test has power b
· 1 / V is the statistical information
contributed by each sampling unit
