Funding for this research was provided by:
Universitätsklinikum Hamburg-Eppendorf (UKE)
Received: 11 November 2020
Accepted: 11 February 2021
First Online: 1 April 2021
: We obtained ethical approval from the Ethics Committee of the Hamburg Medical Association, Germany, on April 7th, 2015 (approval number PV4763). All methods were carried out and are described in accordance with the <i>Strengthening the Reporting of Observational Studies in Epidemiology</i> (STROBE) checklist for cross-sectional studies (Version 4, 2007). All methods were carried out according to the <i>Declaration of Helsinki—Ethical Principles for Medical Research Involving Human Subjects</i> (WMA, 2013). Informed consent was obtained from all the participants involved in the study. Participation was completely voluntary and anonymous. Participants were notified before participation that their informed consent would be assumed if they voluntarily returned a completed response form.
: Not applicable.
: The authors declare that they have no competing interests.