Data sources We obtained individual level data from 13 cohort studies participating in the Individual-Participant-Data Meta-analysis in Working Populations Consortium.
Study participants were women from 49 studies participating in BCAC: 38 from populations of predominantly European ancestry, 9 of Asian women and 2 of African American women (Table 1 and Supplementary Table 1).
In this analysis, participants were restricted to 83,087 women of European ancestry from 37 case control studies participating in BCAC, including 42,510 invasive breast cancer cases with stage I III disease and 40,577 cancer-free controls.
A recent survey reported by AHRQ found that 34%% of studies participating in the survey recruited less than 75%% of their planned sample, leading to reductions in the statistical power of studies [19].
Nine studies participating in this pooled analysis (Tables 4 and S4) included 3601 women with primary incident endometrial carcinoma and 5275 women who were free of endometrial cancer and did not have history of hysterectomy.
Unpublished results were then acquired through analysis of data from studies participating in the Healthy Ageing across the Life Course (HALCyon) collaboration (www.halcyon.ac.uk) and contact with other study investigators.
