title: Response.
authors.affiliation: Cancer Epidemiology Unit,  University of Oxford, Oxford, UK.
authors.forename: Ruth C
authors.initials: RC
authors.lastname: Travis
authors.affiliation: Cancer Epidemiology Unit,  University of Oxford, Oxford, UK.
authors.forename: Gillian K
authors.initials: GK
authors.lastname: Reeves
authors.affiliation: Clinical Trial Service Unit and Epidemiological Studies Unit,  University of Oxford, Oxford, UK.|Nuffield Department of Population Health, University of Oxford, Oxford, UK.
authors.forename: Richard
authors.initials: R
authors.lastname: Peto
authors.affiliation: Cancer Epidemiology Unit,  University of Oxford, Oxford, UK.
authors.forename: Timothy J
authors.initials: TJ
authors.lastname: Key
authors.affiliation: Cancer Epidemiology Unit,  University of Oxford, Oxford, UK.
authors.forename: Valerie
authors.initials: V
authors.lastname: Beral
mesh_terms: D001943:Breast Neoplasms; D006801:Humans; D011446:Prospective Studies; D000073577:Shift Work Schedule