Case-crossover study
DUN Zhong-jun
S China J Prev Med . 2017, (2): 191 -192 .  DOI: 10.13217/j.scjpm.2017.0191

Copyright © 2019 South China Journal of Preventive Medicine, All Rights Reserved.
E-mail: gdsjkzx_hnyfyx@gd.gov.cn
Powered by Beijing Magtech Co. Ltd