Table 1 Sample size calculations with different levels of intracluster correlation coefficient (ICC)a
Adherence (proportion of women at least 85% adherent at 12 months postpartum) | |||||
ICC | Control | Difference | Intervention | Number of sites | Total sample |
0.06 | 55% | 25% | 80% | 10 | 680 |
0.07 | 55% | 25% | 80% | 12 | 772 |
0.08 | 55% | 25% | 80% | 12 | 866 |
0.09 | 55% | 25% | 80% | 14 | 958 |
0.10 | 55% | 25% | 80% | 16 | 1050 |
0.11 | 55% | 25% | 80% | 16 | 1144 |
0.12 | 55% | 25% | 80% | 18 | 1236 |
Retention in care (proportion of women with an HIV visit within last 90 days at 12 months postpartum) | |||||
ICC | Control | Difference | Intervention | Number of sites | Total sample |
0.06 | 48% | 25% | 73% | 10 | 734 |
0.07 | 48% | 25% | 73% | 12 | 834 |
0.08 | 48% | 25% | 73% | 14 | 934 |
0.09 | 48% | 25% | 73% | 14 | 1036 |
0.10 | 48% | 25% | 73% | 16 | 1136 |
0.11 | 48% | 25% | 73% | 18 | 1236 |
0.12 | 48% | 25% | 73% | 20 | 1336 |