February, 2003
© 2000, 2001 Scott S. Emerson, M.D., Ph.D.
Session 3: 54
Measuring Study Time
Example: Comparison with error spending approach using interpolated error spending function
The stopping boundary based on the error spending function will not agree exactly with the curve for the original design, because the error spending function is not linear for this design.
Had the monitoring occurred at the prespecified time, the two curves would agree.