by Meng, Qun, Dr, Xu, Ling, MPhil, Zhang, Yaoguang, MPH, Qian, Juncheng, MPH, Cai, Min, MSc, Xin, Ying, MPH, Gao, Jun, MPH, Xu, Ke, PhD, Boerma, J Ties, MD, Barber, Sarah L, DPH
Published in The Lancet (British edition) (03.03.2012)