Article History
Received: 23 February 2018
Accepted: 1 August 2018
First Online: 13 August 2018
Ethics approval and consent to participate
: The protocol for this study was approved by the ethics committee of Bielefeld University. Participants gave their informed consent by clicking on a button before proceeding with the online-based survey.
: Not applicable.
: FF serves on the Editorial Board of BMC Public Health as Associate Editor.
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