Received: 13 August 2019
Accepted: 26 November 2019
First Online: 7 December 2019
Ethics approval and consent to participate
: All procedures performed in studies 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. All participants were informed about the purpose of the study and oral and written consent was obtained. In the cases of children under 16 years old, consent for participation was obtained from their parent or guardian. The Institutional Ethics Committee of University Medical Center Göttingen approved the study and waiver of written informed consent (reference number 21/9/17).
: Not applicable.
: The authors declare that they have no competing interests.