Institution: | (1) Biostatistics Group, School of Epidemiology & Health Sciences, Stopford Building, Oxford Road, Manchester M13 9PT, UK;(2) Present address: Social Medicine Department, Rafsanjan Medical School, Iran;(3) Evidence Based Population Health Unit, School of Epidemiology & Health Sciences, The University of Manchester, UK;(4) School of Psychiatry, The University of Manchester, UK |