Funding for this research was provided by:
National Natural Science Foundation of China (81470927, 81800667)
1.3.5 project for disciplines of excellence, West China Hospital, Sichuan University (ZY2016104)
Text and Data Mining valid from 2019-01-02
Received: 11 September 2018
Accepted: 23 November 2018
First Online: 2 January 2019
Compliance with ethical standards
: Meta-analysis does not require ethical review.
: Meta-analysis does not require informed consent.
: The authors declare that they have no conflict of interest.