Funding for this research was provided by:
CZ (not applicable)
Received: 19 April 2018
Accepted: 14 December 2018
First Online: 8 January 2019
Ethics approval and consent to participate
: The medical ethics committee of Erasmus Medical Centre, Rotterdam, the Netherlands, determined that the rules stipulated in the Medical Research Involving Human Subjects Act did not apply to this study (protocol no. MEC-2018-021). Written informed consent to participate in the study was obtained from all participants.
: Not applicable.
: Prof.dr. Anna Petra Nieboer works as an Associate Editor of BMC Health Services Research. Other than that the authors declare that they have no competing interest.
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