Received: 24 December 2019
Accepted: 18 May 2020
First Online: 10 June 2020
Ethics approval and consent to participate
: The design of the study was approved on October 10th 2011 by the medical ethics committee of the medical center of the Radboud University in Nijmegen, the Netherlands (CMO Radboud UMC: 2013/226). Prior to participation, all participants provided written informed consent after a clear explanation of the study procedures.
: Not applicable.
: The authors declare that they have no competing interests other than TvS receiving royalties from the DEBQ and the EDI-3 and RDC being a paid statistical consultant for Health Outcomes Solutions, Winter Park, Florida.