Funding for this research was provided by:
The Netherlands ALS Foundation (2014-27)
Text and Data Mining valid from 2018-05-02
Received: 6 December 2017
Accepted: 16 April 2018
First Online: 2 May 2018
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 is voluntary and all respondents will provide written informed consent before inclusion. Any amendments to the protocol will be submitted to and approved by the Medical Ethics Committee of the University Medical Center Utrecht.
: The authors declare that they have no competing interests.
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