Received: 23 December 2018
Accepted: 30 July 2019
First Online: 28 August 2019
Ethics approval and consent to participate
: No ethical approval was needed for the study; as the participants were not physically involved in the research and the questionnaires were not mentally exhausting, the study was not subject to the Dutch Medical Research (Human Subject) Act. All patients participating in the study gave written informed consent.
: Not applicable.
: All authors, A.N. van Smoorenburg, D.F.L. Hertroijs, T. Dekkers, A.M.J. Elissen and M. Melles, declare that they have no conflict of interest.