[1] Natl Univ Polyclin, Natl Univ Hlth Syst, 1 Jurong East St 21,Tower C,Level 1M, Singapore 609606, Singapore
[2] Natl Univ Hlth Syst, Dept Family Med, Singapore, Singapore
[3] Natl Univ Singapore, Yong Loo Lin Sch Med, Div Family Med, Singapore, Singapore
[4] Natl Univ Singapore, Alice Lee Ctr Nursing Studies, Yong Loo Lin Sch Med, Singapore, Singapore
[5] Natl Univ Hlth Syst, Natl Univ Hosp, Dept Psychol Med, Singapore, Singapore