Received: 5 January 2019
Accepted: 27 December 2019
First Online: 20 January 2020
Ethics approval and consent to participate
: As patient data were initially collected as part of routine care and no additional examination was performed, agreement of an ethics committee was not required according to the French regulation at the time of the start of the study but the database was declared to the CNIL (Commission Nationale Informatique et Liberté). In French public hospitals patients are informed that routine data can be used for research purposes. All data were completely anonymized in each of the centres that participated in the study.
: Not applicable.
: The authors declare that they have no competing interests.