Received: 6 July 2018
Accepted: 4 January 2019
First Online: 14 January 2019
Ethics approval and consent to participate
: The study was approved by the research ethics committee of Geneva, Switzerland. <i>Commission Cantonale d’Ethique de la Recherche (CCER) (identifier 2016–00104).</i>Data from this retrospective data were anonymized and manuscript does not contain data from any individual person. Therefore, the need for consent was deemed unnecessary according to CCER regulations.
: The authors declare that they have no competing interests.
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