[1] Univ Basel Hosp, Basel Inst Clin Epidemiol & Biostat, CH-4031 Basel, Switzerland
[2] Univ Basel Hosp, Clin Transplantat Immunol & Nephrol, CH-4031 Basel, Switzerland
[3] Erasmus MC, Dept Publ Hlth, Rotterdam, Netherlands
[4] Wellcome Trust Major Overseas Programme, Ho Chi Minh City, Vietnam
[5] Oxford Univ Clin Res Unit, Ho Chi Minh City, Vietnam