Document is current

Article History

Received: 14 May 2018

Accepted: 28 August 2018

First Online: 1 October 2018

Ethics approval and consent to participate

: The study protocol was approved by the Ethics Committee at Kyorin University Hospital (approval number 858) and conducted in accordance with the Declaration of Helsinki. The study design was retrospective and noninterventional, so informed consent was not deemed necessary.

: Not applicable.

: The authors declare that they have no competing interests.

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