|
Required Sample Size for Intermediate-Risk Group Patients with Two Interim Analyses
|
|---|
|
Effect size
| |
α = 0.05 with 1:1 Group Ratio
|
α = 0.05 with 1:2 Group Ratio
|
|---|
|
Power
|
80%
|
90%
|
80%
|
90%
|
|---|
|
10%
|
N1
|
315
|
438
|
235
|
326
|
|
N2
|
315
|
438
|
470
|
652
|
|
Total
|
630
|
876
|
705
|
978
|
|
15%
|
N1
|
140
|
194
|
104
|
145
|
|
N2
|
140
|
194
|
208
|
290
|
|
Total
|
280
|
388
|
312
|
435
|
|
20%
|
N1
|
78
|
108
|
58
|
81
|
|
N2
|
78
|
108
|
116
|
162
|
|
Total
|
156
|
216
|
174
|
243
|
|
25%
|
N1
|
49
|
67
|
37
|
51
|
|
N2
|
49
|
67
|
74
|
102
|
|
Total
|
98
|
134
|
111
|
153
|
|
30%
|
N1
|
33
|
45
|
25
|
35
|
|
N2
|
33
|
45
|
50
|
70
|
|
Total
|
66
|
90
|
75
|
105
|
|
35%
|
N1
|
23
|
32
|
18
|
25
|
|
N2
|
23
|
32
|
36
|
50
|
|
Total
|
46
|
64
|
54
|
75
|
|
40%
|
N1
|
17
|
23
|
13
|
18
|
|
N2
|
17
|
23
|
26
|
36
|
|
Total
|
34
|
46
|
39
|
54
|
- N1: sample size for the standard care arm. N2: sample size for the treatment arm
- Response rate = 40%
- For 80% power: probability of rejection at each look: 1st look p < 0.002, futility look p > 0.835, 2nd look p < 0.014, futility look p > 0.312, final look p < 0.046
- For 90% power: probability of rejection at each look: 1st look p < 0.002, futility look p > 0.830, 2nd look p < 0.014, futility look p > 0.298, final look p < 0.046
- ρ = 3.0
- Bold indicates recommended sample size with suggested parameters
