Received: 17 July 2018
Accepted: 7 January 2019
First Online: 11 January 2019
Ethics approval and consent to participate
: The Medical Ethics Committee of the Academic Medical Center, Amsterdam, the Netherlands, approved this retrospective study (number W18_010 # 18.021) and waived the need for individual patient informed consent based on the anonymous nature of the data reporting.
: Not applicable.
: The authors declare that they have no competing interests.
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