Disease Status (D) | Metal-workers Z (τ i j ) | Fixed number of subjects to be included in Phase Two (n ij ) | Expected Phase One numbers of subjects to be screened (N ij ) | Expected Proportion of MWF exposure within strata § X(π i jk ) | Expected distribution of subjects by MWF in Phase Two |
---|---|---|---|---|---|
 |  |  | N0 = Max(160/20%, 40/80%) = 800 |  |  |
Control | No (80%*) | 40 | 800*80% = 640 | No (97.5%*) | 40*97.5% = 39 |
 |  |  |  | Yes (2.5%*) | 40*2.5% = 1 |
 | Yes (20%*) | 160 | 800*20% = 160 | No (75%*) | 160*75% = 120 |
 |  |  |  | Yes (25%*) | 160*25% = 40 |
 |  |  | N1 = Max(85/23.4%, 20/76.6%) = 364 |  |  |
Case | No (76.6%#) | 20 | 364*76.6% = 278.8 | No (95.1%#) | 20*95.1% = 19.02 |
 |  |  |  | Yes (4.9%#) | 20*4.9% = 0.98 |
 | Yes (23.4%#) | 85 | 364*23.4% = 85 | No (60%#) | 85*60% = 51 |
 |  |  |  | Yes (40%#) | 85*40% = 34 |