affiliation not provided to SSRN, University of Geneva - Institute of Global Health, affiliation not provided to SSRN, affiliation not provided to SSRN, affiliation not provided to SSRN, American University of Beirut - Department of Internal Medicine, American University of Beirut - Clinical Research Institute, Lanzhou University, Lanzhou University, Lanzhou University, Chongqing Medical University, Lanzhou University, Lanzhou University, Chinese Academy of Medical Sciences & Peking Union Medical College (CAMS & PUMC) - School of Public Health, Lanzhou University - School of Basic Medical Sciences and affiliation not provided to SSRN