Gao, Shu-tao
Lv, Zheng-tao
Zhou, Chuan-kun
Mao, Chao
Sheng, Wei-bin
Article History
Received: 23 December 2017
Accepted: 26 April 2018
First Online: 10 May 2018
Ethics approval and consent to participate
: Not applicable as this is a meta-analysis of previously published papers.
: The authors declare that they have no competing interests.
: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.