Received: 11 August 2017
Accepted: 3 July 2018
First Online: 3 August 2018
Ethics approval and consent to participate
: In each institution, the study was approved by the institutional research ethics committee in accordance with local ethical regulations. Informed consent was not required due to the observational and anonymous nature of data collection.
: Not applicable.
: The authors declare that they have no competing interests.
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