Received: 14 February 2019
Accepted: 11 July 2019
First Online: 7 August 2019
Ethics approval and consent to participate
: Ethical approval was obtained from the Medical Ethics Committee of the Atrium Hospital in Heerlen, The Netherlands (15-N-169). All participants provided written informed consent prior to participation.
: Not applicable.
: The authors declare that they have no competing interests.