1. Department of Epidemiology and Biostatistics; School of Public Health; Peking University Health Science Centre; Beijing; China
2. Hong Kong Cochrane Centre, School of Public Health, Faculty of Medicine; Chinese University of Hong Kong; Hong Kong; China
3. National Institute for Health and Clinical Excellence; London; UK
4. The Finnish Medical Society Duodecim; Helsinki; Finland
5. Institute of Basic Research in Clinical Medicine; China Academy of Chinese Medical Sciences; Beijing; China