Received: 9 October 2019
Accepted: 28 February 2020
First Online: 16 March 2020
Ethics approval and consent to participate
: Medical ethical approval was waivered by the local Medical Ethics Committee of the Amsterdam University Medical Center [reference number 2018.259], because this study was observational and only requested answering validated questionnaires from the participants. In addition, the study was performed in compliance with the principles outlined in the Declaration of Helsinki on ethical principles for medical research involving human subjects [CitationRef removed]. Verbal consent was obtained from all participants and registered in the electronic patient file. Following consent, patients visited an online platform where a digital consent was recorded, before answering questions regarding demographic information and the PROMs.
: All presented data in this study cannot be traced to individual patients and do not compromise anonymity. Therefore consent for publication is not applicable.
: CBT is president of the PROMIS Health Organization, a charitable foundation that aims to advance the science of health outcomes assessment through the use of PROMIS. CBT and LDR are coordinators of the Dutch-Flemish PROMIS National Center. AK is one of the developers of the US PROMIS-UE v2.0 item bank. The other authors declare they have no competing interests.