Funding for this research was provided by:
Received: 5 September 2018
Accepted: 11 February 2019
First Online: 19 February 2019
Ethics approval and consent to participate
: This study did not require review by an ethics committee under the Dutch Medical Research Involving Human Subjects Act, since it did not involve imposing any interventions or actions and no patients were involved. Informed consent was assumed on return of the survey.
: Not applicable.
: The authors declare that they have no competing interests.
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