Table 3 Sequential testing on equality of areas under ROC curves [17]
Number of interim analyses | P value (sample size) and respective significance level at analysis time point | |||
|---|---|---|---|---|
Interim analysis 1 | Interim analysis 2 | Interim analysis 3 | Final analysis | |
0 | – | – | – | 0.0189 (N = 100) α 1 = 0.05 |
1 | 0.1557 (N = 50) α 0.5 = 0.025 | – | – | 0.0189 (N = 100) α 1 = 0.05 |
2 | 0.0669 (N = 33) α 0.33 = 0.0167 | 0.0577 (N = 67) α 0.67 = 0.0333 | – | 0.0189 (N = 100) α 1 = 0.05 |
3 | 0.0174 (N = 25) α 0.25 = 0.0125 | 0.1557 (N = 50) α 0.5 = 0.025 | 0.0395 (N = 75) α 0.75 = 0.0375 | 0.0189 (N = 100) α 1 = 0.05 |