Received: 15 January 2018
Accepted: 3 May 2018
First Online: 1 August 2018
Ethics approval and consent to participate
: Research committee approval was not required as it is a retrospective study with no identifying information of any patients. This study was not registered as a trial because it is a retrospective study that does include any involvement in the management or follow-up of patients and as such did not require registering.
: Not applicable.
: The authors declare that they have no competing interests.
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