[Yu, Tianhua] Jilin Univ, Sch Publ Hlth, Changchun, Jilin, Peoples R China.^[Yu, Tianhua] Jilin Univ, China Japanese Friendship Hosp, Dept Blood Transfus, Changchun, Jilin, Peoples R China.^[Xu, Chang] Cent China Normal Univ, Sch Life Sci, Wuhan, Hubei, Peoples R China.^[Zhang, Xinyu] Columbia Univ, Grad Sch Art & Sci Stat, New York, NY 10027 USA.