Funding for this research was provided by:
Received: 29 November 2018
Accepted: 31 January 2019
First Online: 19 February 2019
Ethics approval and consent to participate
: Under the Dutch Medical Research Involving Human Subjects Act, ethical approval was not required for the posthumous collection of anonymous patient data [CitationRef removed]. Informed consent of the certifying physicians was assumed on return of the survey.
: Not applicable
: The authors declare that they have no competing interests.
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