Received: 23 October 2018
Accepted: 22 November 2018
First Online: 7 December 2018
Ethics approval and consent to participate
: Ethical approval was obtained from the Central Ethical Review Board in Stockholm (2015/2162–31). As this investigation was a retrospective study that reviewed medical records without revealing the patient’s private information, informed consent was waived.
: Not applicable.
: The authors declare that they have no competing interests.
: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.