Received: 15 February 2019
Accepted: 13 May 2019
First Online: 4 June 2019
Ethics approval and consent to participate
: The VITDAL trial was approved by the Ethics Committee of the Medical University of Graz and the Austrian Agency for Health and Food Safety (NCT01130181).
: Written informed consent was obtained directly from the patients or from a legal surrogate.
: The authors declare that they have no competing interests.
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