Number of women required for a double blinded efficacy trial on preventive HPV16 vaccination with cervical intraepithelial neoplasia grade III and invasive cervical cancer as the end point
| Number of vaccinees at a given VE | |||
|---|---|---|---|
| Age group (years) | CIN III+ attack rate % | 90% | 70% |
| ≤18 | 0.33 | 6 446 | 12 592 |
| 18–19 | 0.44 | 4 832 | 9 436 |
| 20–24 | 0.21 | 10 138 | 19 804 |
| <25 | 0.28 | 7 600 | 14 846 |