Funding for this research was provided by:
Conseil Régional du Limousin
Received: 29 March 2017
Accepted: 14 December 2017
First Online: 25 January 2018
Ethics approval and consent to participate
: The study was approved by the French IPC. The Committee reference number is 2012-A01456-37. The investigators will obtain written informed consent from all participants in the study.
: Not applicable.
: The authors declare that they have no competing interests.
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