Funding for this research was provided by:
Bronovo Research Fund (N/A)
Text and Data Mining valid from 2018-03-16
Received: 10 December 2017
Accepted: 7 February 2018
First Online: 16 March 2018
Ethics approval and consent to participate
: The Institutional Review Board (IRB) of Leiden University Medical Centre, Leiden, the Netherlands reviewed the study and exempted it from IRB approval. All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards. For this retrospective study, formal consent is not required. This article does not contain any studies with animals performed by any of the authors.
: The authors declare that they have no competing interests.
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