Funding for this research was provided by:
Deutsche Forschungsgemeinschaft (Sonderforschungsbereich 1015)
Article History
First Online: 11 November 2019
Compliance with Ethical Standards
: Written informed consent or written parental consent in the case of minors was collected from all participants. The study protocol was submitted to the Ethics Committee of the Medical Center – University of Freiburg, which declared that ethical assessment is not compulsory for this study. All procedures involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.
: The authors declare that they have no conflict of interest.