[1] Natl Univ Singapore, NUS Yong Loo Lin Sch Med, Dept Anaesthesia, Singapore, Singapore
[2] Natl Univ Singapore, NUS Yong Loo Lin Sch Med, Natl Univ Hlth Syst, Emergency Med, Singapore, Singapore
[3] Natl Univ Singapore, NUS Yong Loo Lin Sch Med, Dept Family Med, Natl Healthcare Grp, Singapore, Singapore
[4] Natl Univ Singapore, NUS Yong Loo Lin Sch Med, Singapore Clin Res Inst, Epidemiol, Singapore, Singapore
[5] Natl Univ Singapore, NUS Yong Loo Lin Sch Med, Ctr Med Educ CenMED, Singapore, Singapore