Received: 18 July 2018
Accepted: 30 July 2018
First Online: 21 September 2018
Ethics approval and consent to participate
: Data collection and analyses were conducted in accordance with the French national guidelines: under French law, a retrospective study using data from medical charts requires only a declaration to the Commission nationale Informatique et Libertés. The hospital’s computerised database was declared at this commission. There is no requirement for declaration to an ethic committee.
: Not applicable.
: The authors declare that they have no competing interests.
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