Funding for this research was provided by:
Austrian research funds (FWF-TRP-188)
Received: 25 November 2017
Accepted: 9 February 2018
First Online: 7 March 2018
Ethics approval and consent to participate
: The study was approved by the Ethics committee at Medical University Innsbruck, Austria (study number AN2014-0277). Patients in the database provided written informed consent, for patients who were retrospectively analysed, no consent to participate was obtained. This was approved by the Ethics committee at Medical University Innsbruck, Austria.
: Not applicable.
: The authors declare that they have no competing interests.
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