Author contributions
Study concept and design: SYQ, YC;
Acquisition of data: YJQ, HNX and HLK;
Analysis and interpretation of data: YJQ, HLK and HNX;
Drafting of the manuscript: YJQ, HLK;
Critical revision of the manuscript for important intellectual content: YC, SYQ;
Statistical analysis: YJQ, HNX;
Obtaining funding: SYQ;
Administrative, technical, or material support: SYQ, YC and ZZH;
Supervision: SYQ;