Table 1. Baseline clinical characteristics of involved groups.

	Group 1 (n = 285)	Group 2 (n = 225)	Group 3 (n = 318)
	No (%)	No (%)	No (%)
Age
≤35	57 (20.0)	53 (23.6)	78 (24.5)	0.224
36–50	161 (56.5)	136 (60.4)	174 (54.7)
>50	67 (23.5)	36 (16)	66 (20.8)
Smoking
Never	270 (94.7)	208 (92.4)	307 (96.5)	0.108
ever	15 (5.3)	17 (7.6)	11 (3.5)
HPV status
HPV+	285 (100)	225 (100)	0 (0)
HPV−	0 (0)	0 (0)	318 (100)
Clinical stage*
Stage 0	142 (49.8)
Stage I	108 (37.9)
Stage II	28 (9.8)
Stage III	6 (2.1)
Stage IV	1 (0.4)

Note: ^* According to the International Federation of Gynecology and Obstetrics classification.