[1] Chonnam Natl Univ, Sch Med, Dept Prevent Med, Kwangju 501746, South Korea
[2] Korea Hlth Ind Dev Inst, Dept Overseas Hosp Consulting, Seoul 156800, South Korea
[3] Seonam Univ, Coll Med, Dept Prevent Med, Namwon 590711, Jeollabukdo, South Korea
[4] Chonnam Natl Univ Hosp, Gwangju Jeonnam Reg Cardiocerebrovasc Ctr, Kwangju 501746, South Korea
[5] Chosun Univ, Sch Med, Dept Prevent Med, Kwangju 501759, South Korea
[6] Chonnam Natl Univ, Hwasun Hosp, Jeonnam Reg Canc Ctr, Jeollanamdo 519809, South Korea