[1] Duke NUS Med Sch, Ctr Quantitat Med, Singapore, Singapore
[2] Natl Univ Singapore, Dept Stat & Data Sci, Singapore, Singapore
[3] Duke NUS Med Sch, Ctr Quantitat Med, 8 Coll Rd,Level 6,06-31, Singapore 169857, Singapore
[4] Duke NUS Med Sch, Program Hlth Serv & Syst Res, 8 Coll Rd,Level 6,06-31, Singapore 169857, Singapore