[1] Taipei Med Univ, Sch Oral Hyg, Coll Oral Med, Taipei, Taiwan
[2] Univ Dundee, Ninewells Hosp & Med Sch, Ctr Res Canc Prevent & Screening, Dundee DD1 9SY, Scotland
[3] Chang Gung Univ, Dept & Grad Inst Hlth Care Management, Tao Yuan, Taiwan
[4] Kainan Univ, Sch Healthcare Management, Dept Hlth Ind Management, Tao Yuan, Taiwan
[5] Keelung City Publ Hlth Bur, Keelung, Taiwan
[6] Tainan City Publ Hlth Bur, Tainan, Taiwan
[7] Shin Kong Wu Ho Su Mem Hosp, Div Gastroenterol, Dept Internal Med, Taipei, Taiwan
[8] Natl Taiwan Univ, Coll Med, Dept Internal Med, Taipei, Taiwan
[9] Natl Taiwan Univ, Grad Inst Epidemiol & Prevent Med, Coll Publ Hlth, Taipei 10764, Taiwan