1. Health Services Research Unit, Singapore General Hospital, Singapore 169608, Singapore
2. Saw Swee Hock School of Public Health, National University of Singapore, Singapore 117549, Singapore
3. NUS Yong Loo Lin School of Medicine, Singapore 117597, Singapore
4. School of Medicine, Dentistry and Nursing, University of Glasgow, Glasgow G12 8QQ, UK
5. Department of Psychiatry, Singapore General Hospital, Singapore 169608, Singapore
6. SingHealth Duke-NUS Medicine Academic Clinical Programme, Duke-NUS Medical School, Singapore 169857, Singapore
7. Health Services and Systems Research, Duke-NUS Medical School, Singapore 169857, Singapore