Seroprevalence of human papillomaviruses and Chlamydia trachomatis and cervical cancer risk: nested case-control study.
A nested case–control study of invasive and in situ cervical cancer was performed within a community-based cohort of 13 595 Taiwanese women assembled in 1991, with a follow-up period of 9 years. Baseline serum or plasma samples were analysed for antibodies against human papillomavirus (HPV) types 6, 16 and 18 and Chlamydia trachomatis. In total, 114 cases (42 incident cases identified during follo