Funding for this research was provided by:
Motor Neurone Disease Association
Medical Research Council (MR/L501529/1, MR/R024804/1)
Economic and Social Research Council (ES/L008238/1)
Horizon 2020 Framework Programme (633413)
Received: 13 March 2019
Accepted: 16 April 2019
First Online: 17 July 2019
Ethics approval and consent to participate
: patients were analysed under ethical approval reference 08/H0405/60 from the Trent Research ethics committee.
: Not applicable
: The authors declare that they have no competing interests.
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