Document is current

Article History

Received: 10 September 2017

Accepted: 16 January 2018

First Online: 21 February 2018

Ethics approval and consent to participate

: This study protocol was approved by the local ethics committee at Japanese Red Cross Musashino Hospital named Clinical Research Judging Committee.

: Informed consent was obtained from all the participants or their surrogate decisionmakers.

: The authors declare that they have no competing interests.

: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.