Funding for this research was provided by:
Centre for Health North Rhine-Westphalia, Germany (not applicable)
Received: 8 April 2019
Accepted: 5 November 2019
First Online: 26 November 2019
Ethics approval and consent to participate
: The study was submitted to and approved by the institutional ethics committee of the University Medical Faculty in Bonn, Germany (No. 167/17). All participants received information on study procedures, anonymity and confidentiality. Written informed consent was not obtained in order to ensure anonymity but respondents confirmed their willingness to participate in the study by returning the questionnaire.
: Not applicable.
: The authors declare that they have no competing interests.