Characteristics relating to ovarian cancer risk: collaborative analysis of 12 US case-control studies. I. Methods. Collaborative Ovarian Cancer Group.

Data from 12 US case-control studies of ovarian cancer, conducted during the period 1956-1986 and representing some 3,000 cases and 10,000 controls, were pooled and reanalyzed. Separate analyses were conducted for four subgroups of the pooled data: invasive epithelial ovarian cancers in white women; epithelial ovarian cancers of low malignant potential in white women, epithelial ovarian cancers in black women, and nonepithelial ovarian cancers. This paper gives a brief description of the participating studies and describes the methods used in the collaborative analysis.