We found a matchYour institution may have access to this item. Find your institution then sign in to continue.TitleEpidemiologic studies of a necessary causal risk factor: human papillomavirus infection and cervical neoplasia.AuthorsSchiffman, Mark H; Castle, PhilipPublicationJNCI Journal of the National Cancer Institute, 2003, Vol 95, Issue 6, pE2ISSN0027-8874Publication typearticleDOI10.1093/jnci/95.6.e2