[1] Tzu Chi Univ, Coll Med, Hualien, Taiwan
[2] Taichung Tzu Chi Hosp, Dept Internal Med, Div Hepatogastroenterol, Taichung, Taiwan
[3] China Med Univ, Coll Publ Hlth, Dept Publ Hlth, Taichung, Taiwan
[4] China Med Univ, Coll Med, Dept Med, Taichung, Taiwan
[5] China Med Univ Hosp, Dept Family Med, Taichung, Taiwan