Funding for this research was provided by:
Netherlands ALS Foundation (201427)
Text and Data Mining valid from 2019-06-15
Received: 3 January 2019
Accepted: 28 May 2019
First Online: 15 June 2019
Ethics approval and consent to participate
: This study has been approved by the Medical Ethics Committee of the University Medical Center Utrecht under file number 16–273-D. Participation was voluntary and all respondents provided written informed consent before inclusion.
: Not applicable.
: The authors declare that they have no competing interests.