About the Authors

Annika Waldmann

Annika.Waldmann@uksh.de

Affiliation Institute of Social Medicine and Epidemiology, University of Luebeck, Luebeck, Germany

Daniel Schubert

Affiliation Institute of Social Medicine and Epidemiology, University of Luebeck, Luebeck, Germany

Alexander Katalinic

Affiliations Institute of Social Medicine and Epidemiology, University of Luebeck, Luebeck, Germany, Institute of Cancer Epidemiology, University of Luebeck, Luebeck, Germany

Competing Interests

We have the following interests: Druckerei Radtke, Luebeck, supported our study by bearing the printing costs for our questionnaires [http://www.radtke-druck.de/. There are no patents, products in development or marketed products to declare. This does not alter our adherence to all the PLOS ONE policies on sharing data and materials, as detailed online in the guide for authors.

Author Contributions

Conceived and designed the experiments: AW AK. Performed the experiments: AW DS. Analyzed the data: AW DS. Wrote the manuscript: AW DS AK.