Received: 6 April 2020
Accepted: 16 July 2020
First Online: 1 August 2020
Ethics approval and consent to participate
: In accordance with the applicable laws in France and Switzerland and since no patients were involved in this study, no ethical approval was required.
: Not applicable.
: The authors declare that they have no competing interests. Dagmar M Haller is a member of the Editorial Board (Associate Editor) of BMC.