[1] Imperial Coll London, Dept Surg & Canc, London, England
[2] Natl Univ Singapore, Yong Loo Lin Sch Med, Dept Med, Singapore, Singapore
[3] Natl Univ Singapore Hosp, Dept Obstet & Gynaecol, Singapore, Singapore
[4] Natl Univ Singapore, Yong Loo Lin Sch Med, Biostat Unit, Singapore, Singapore
[5] Natl Univ Heart Ctr, Dept Cardiol, Singapore, Singapore
[6] Natl Univ Hlth Syst, Natl Univ Polyclin, Pioneer Polyclin, Singapore, Singapore
[7] Inst Mental Hlth, Singapore, Singapore
[8] Natl Univ Singapore, Yong Loo Lin Sch Med, Dept Psychol Med, Singapore, Singapore
[9] Inst Mental Hlth, Dept Forens Psychiat, Singapore, Singapore
[10] Alexandra Hosp, Div Hlth Ageing, Singapore, Singapore
[11] Ng Teng Fong Gen Hosp, Dept Geriatr Med, Singapore, Singapore
[12] Natl Univ Singapore, Yong Loo Lin Sch Med, Dept Surg, Singapore, Singapore
[13] Natl Univ Singapore Hosp, Emergency Med Dept, Singapore, Singapore
[14] Polish Hosp Federat, Warsaw, Poland
[15] Med Univ Warsaw, Dept Econ Hlth & Med Law, Warsaw, Poland