1. Division of Cancer Epidemiology, German Cancer Research Center (DKFZ), Heidelberg, Germany;
2. Department of Statistics and Probability, Michigan State University, East Lansing, MI, USA;
3. Department of Medical Biometry and Epidemiology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany;
4. Metabolomics Core Technology Platform, Centre for Organismal Studies, University of Heidelberg, Heidelberg, Germany;
5. Cancer Epidemiology Group, University Cancer Center Hamburg, University Medical Center Hamburg-Eppendorf, Hamburg, Germany