Author contributions
Conception and design of the study: J.Q.H, G.H.Z, S.J.W and Y.Y.Z. Collection of data: J.Q.H, L.L, Y.Z.X, W.X.G and X.J.L. Analysis and interpretation of data: M.C., B.Z.Z and R.M.X. Drafting of the manuscript: J.Q.H., X.H.G., and B.H. Critical revision of the manuscript for important intellectual content: G.H.Z., S.W.J., and Y.Y.Z. Administrative support and study supervision: Y.Y.Z. All authors reviewed the manuscript.