Funding for this research was provided by:
National Basic Research Program of China (973 Program) (No. 2016YFC1306202)
Wuhan Yellow Crane (2016-01)
Hubei Health and Family Planning Commission (WJ2015MB247)
Text and Data Mining valid from 2020-01-10
Received: 8 May 2019
Accepted: 5 September 2019
First Online: 10 January 2020
Compliance with ethical standards
: The authors declare that they have no competing interests.
: Informed consent was obtained from all individual participants included in the study.