1. Health Services Research Unit, Singapore General Hospital, Singapore 169608, Singapore
2. Saw Swee Hock School of Public Health, National University of Singapore and National University Health System, Singapore 117549, Singapore
3. Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore 308232, Singapore
4. NUS Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117597, Singapore
5. SingHealth Duke-NUS Medicine Academic Clinical Programme, Duke-NUS Medical School, Singapore 169857, Singapore
6. SingHealth Office of Regional Health, Singapore 911532, Singapore