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Article History

Received: 11 September 2018

Accepted: 3 April 2019

First Online: 30 April 2019

Ethics approval and consent to participate

: With regards to ethics considerations, we declared in the ‘<i>Ethics approval and current status on this trial</i>’ item of the ‘Discussion’ section that our study is performed in accordance with the Declaration of Helsinki and has been approved by an appropriate ethics committee. We receive informed consent from all participants as described in the ‘<i>Registration and informed consent</i>’ item of the ‘Methods/Design’ section.

: Not applicable, because we show no individual patient data in our manuscript.

: The authors declare no competing interest regarding this manuscript or the work described herein.

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