Table 2.

Details of efficacy calculations

			Source
	Bivalent vaccine	Quadrivalent vaccine
Reduction in the probability of HPV infection
Assumed proportion of HPV 16/18 in cervical cancer, A	74.9%	74.9%	[7]
Vaccine efficacy-percent reduction in HPV 16/18 persistent infections, B	95.0%	95.0%	[23,27,28,32-40]
Assumed proportion of other high risk HPV in cervical cancer, C	23.4%	23.4%	[7]
Vaccine efficacy-percent reduction in other high risk HPV persistent infections, D	68.4%	32.5%	[30-32]
Calculated reduction in the probability of HPV infection (AxB)+(CxD)	87.2%	78.8%
Corection factor for CIN1
Percent of HPV 1618 in CIN1 cases which are caused by oncogenic HPV, E	37.0%
Correction factor for CIN1, A-E	37.9%
Corection factor for CIN2/3
Percent of HPV 1618 in CIN2/3 cases which are caused by oncogenic HPV, F	52.0%
Correction factor for CIN2/3 A-F	22.9%