[1] Beijing Jiaotong Univ, Sch Econ & Management, 3 Shangyuancun, Beijing 100044, Peoples R China
[2] Univ Toronto, Inst Hlth Policy Management & Evaluat, Hlth Sci Bldg,155 Coll St,Suite 425, Toronto, ON M5T 3M6, Canada
[3] Shandong Univ Finance & Econ, Sch Insurance, 40 Shungeng Rd, Jinan 250000, Peoples R China