Table 1 Sample size calculation
Age group(y/o) | Incidence of HPV 16/18 infection | Vaccine effectiveness | Frequency ratio | Exposure group | Non-exposure group | Sample size for effectiveness calculation | Targeting recruitment number |
|---|---|---|---|---|---|---|---|
9–20 | 0.02 | 0.83 | 1:1 | 661 | 661 | 1322 | 1890 |
21–30 | 0.02 | 0.66 | 1:1 | 1208 | 1208 | 2416 | 3452 |
31–45 | 0.02 | 0.50 | 1:1 | 2371 | 2371 | 4742 | 6776 |
Total | - | - | - | 4240 | 4240 | 8480 | 12,118 |