[1] Johannes Gutenberg Univ Mainz, Inst Med Biostat Epidemiol & Informat, D-55131 Mainz, Germany
[2] German Canc Res Ctr, Environm Epidemiol Unit, Heidelberg, Germany
[3] Univ Bielefeld, Fac Publ Hlth, Dept Epidemiol & Int Publ Hlth, Bielefeld, Germany
[4] Danish Canc Soc, Inst Canc Epidemiol, Copenhagen, Denmark