Are the Two Human Papillomavirus Vaccines Really Similar? A Systematic Review of Available Evidence: Efficacy of the Two Vaccines against HPV

Table 3

Baseline characteristics of women enrolled in the four studies presented in the meta-analysis.

Study [reference]	Age mean (SD)		HPV 16 positivity at enrolment (%)				HPV 18 positivity at enrolment (%)				Lifetime number of sexual partners (median)			Smoking status (%)		Chlamydia trachomatis (%)		Hormonal contraceptive use (%)		Cytological abnormality at entry (%)
			DNA		Serology		DNA		Serology
	V	C	V	C	V	C	V	C	V	C		V	C	V	C	V	C	V	C	V	C
GSK [11, 12, 28]	20 ± 3	21 ± 3	NR	NR	NR	NR	NR	NR	NR	NR		NR	NR	NR	NR	NR	NR	NR	NR	NR	NR
PATRICIA [13, 27]	20 ± 3	20 ± 3	14	14	2	1	11	10	1	1	0	4%	4%	30	30	6	5	59	61	10	9
											1	74%	74%
											2	14%	15%
											≥3	8%	8%
FUTURE I [16, 26, 30]	20 ± 2	20 ± 2	9	8	12	12	3	3	3	3		2	2	26	26	4	5	58	57	11	12
FUTURE II [17, 26, 30]	20 ± 2	20 ± 2	9	9	11	11	4	4	4	4		2	2	NR	NR	4	4	59	60	12	11

V: vaccine group; C: control group; NR: not reported.
Results are presented as percentage of women stratified by number of sexual partners.