Funding for this research was provided by:
Accepted: 2 September 2020
First Online: 17 September 2020
Compliance with Ethical Standards
: The authors declare that there is no conflict of interest.
: The surveys on which this study is based had been conducted with ethic approvals of the respective universities. For the present work, we used anonymized datasets derived from these studies. Therefore, no additional ethics statement was required.
: Informed consent was obtained from all individual participants included in the study.
: Not applicable