[1] Korea Univ, Med Ctr, Ansan Hosp, Dept Thorac & Cardiovasc Surg,Coll Med, Ansan, South Korea
[2] Univ Nevada, Dept Hlth Care Adm & Policy, Sch Publ Hlth, 4505 S Maryland Pkwy,Box 453023, Las Vegas, NV 89154 USA
[3] Soonchunhyang Univ, Dept Hlth Adm & Management, Asan, South Korea
[4] Mt View Hosp, Dept Phys Med & Rehabil, Las Vegas, NV USA
[5] Southern Nevada Vet Affairs Hlth Syst, Dept Internal Med, North Las Vegas, NV USA
[6] Univ Nevada, Sch Med, Dept Internal Med, Las Vegas, NV 89154 USA