96
Case Study:
Boundaries on Futility Scales
O’Brien-Fleming Efficacy, P=0.8 Futility
Symmetric O’Brien-Fleming
0.177
0.312
0.142
0.592
-0.031
0.124
0.241
0.091
0.500
-0.028
1275
0.063
0.247
0.015
0.648
-0.010
0.023
0.143
0.002
0.500
0.000
850
0.008
0.222
0.000
0.719
0.047
0.000
0.077
0.000
0.500
0.085
425
Futility (rejects -0.0866)
Futility (rejects -0.0855)
0.126
0.077
0.093
0.500
-0.057
0.124
0.077
0.091
0.500
-0.057
1275
0.023
0.015
0.002
0.500
-0.085
0.023
0.015
0.002
0.500
-0.085
850
0.000
0.002
0.000
0.500
-0.170
0.000
0.002
0.000
0.500
-0.171
425
Efficacy (rejects 0.00)
Efficacy (rejects 0.00)
Noninf
Sponsor
Estimat
Design
MLE
Noninf
Sponsor
Estimat
Design
MLE
N
Predictive Power
Conditional Power
Predictive Power
Conditional Power