Required Sample Size for Intermediate-Risk Group Patients with One Interim Analysis
|
---|
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
|
313
|
433
|
234
|
323
|
N2
|
313
|
433
|
468
|
646
|
Total
|
626
|
866
|
702
|
969
|
15%
|
N1
|
139
|
192
|
104
|
143
|
N2
|
139
|
192
|
208
|
286
|
Total
|
278
|
384
|
312
|
429
|
20%
|
N1
|
77
|
106
|
58
|
80
|
N2
|
77
|
106
|
116
|
160
|
Total
|
154
|
212
|
174
|
240
|
25%
|
N1
|
48
|
67
|
37
|
50
|
N2
|
48
|
67
|
74
|
100
|
Total
|
96
|
134
|
111
|
150
|
30%
|
N1
|
32
|
45
|
25
|
34
|
N2
|
32
|
45
|
50
|
68
|
Total
|
64
|
90
|
75
|
102
|
35%
|
N1
|
23
|
31
|
18
|
25
|
N2
|
23
|
31
|
36
|
50
|
Total
|
46
|
62
|
54
|
75
|
40%
|
N1
|
16
|
23
|
13
|
18
|
N2
|
16
|
23
|
26
|
36
|
Total
|
32
|
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 < 0.006, futility look p > 0.709, final look p < 0.047
- For 90% power: probability of rejection at each look: 1st look p < 0.006, futility look p > 0.716, final look p < 0.047
- p = 2.0