Funding for this research was provided by:
Department of Health of Zhejiang Province (2015KYB448)
Text and Data Mining valid from 2018-04-19
Received: 30 October 2017
Revised: 4 March 2018
Accepted: 3 April 2018
First Online: 19 April 2018
Compliance with ethical standards
: The authors declare that they have no competing interests.
: Written informed consent was obtained from all participants in the study.