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Article History

Received: 6 March 2017

Accepted: 1 March 2018

First Online: 15 March 2018

Ethics approval and consent to participate

: This study used retrospective and anonymized administrative data of patients who gave their consent to the use. Therefore this type of study was exempted from approval by an ethics committee.

: Not applicable.

: The authors declare that they have no competing interests.

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