Received: 15 February 2018
Accepted: 16 May 2019
First Online: 11 June 2019
Ethics approval and consent to participate
: Ethical for this retrospective study was given by Albertinen Ethik Kommission (U3–2015). Informed verbal consent was obtained from all individual participants included in the study. The institutional ethical committee approved this procedure because only archival material was investigated and personal identities of the patients were only disclosed to the principal investigator (AP) and the senior author (DKP) of the project.
: Not applicable<b>.</b>
: The authors declare that they have no competing interests.
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