Table 5 Total number of households (children)a required for 80% and 90% power for varying control arm event rates and intra-cluster correlation coefficients
Power | Contacts who develop TB disease by 48 weeks (control arm) (%) | Intra-cluster correlation coefficients | ||
|---|---|---|---|---|
0.05 | 0.1 | 0.15 | ||
80% | 5 | 1056 (2122) | 1108 (2216) | 1158 (2316) |
7 | 742 (1484) | 778 (1556) | 814 (1628) | |
10 | 508 (1016) | 532 (1064) | 556 (1112) | |
90% | 5 | 1414 (2828) | 1480 (2960) | 1548 (3096) |
7 | 994 (1988) | 1040 (2080) | 1088 (2174) | |
10 | 678 (1356) | 710 (1420) | 742 (1484) | |