Efficacy of interferon alfa plus ribavirin versus interferon alone in the treatment of hepatitis B E antigen-positive patients with chronic hepatitis B: Ming-Yang Lai, Graduate Institute of Clinical Medicine, National Taiwan University College of Medicine, Taipei Taiwan; You-Chen Chao, Tri-Service General Hospital, Taipei Taiwan; Tun-Jen Hsiao, Provincial Tao-Yuan Hospital, Tao-Yuan Taiwan; Li-Ying Liao, Taipei Municipal Jen-Ai Hospital, Taipei Taiwan; Sien-Sing Yang, Cathy General Hospital, Taipei Taiwan; K. Arnold Chan, Department of Epidemiology, Harvard School of Public Health, Boston; Ding-Shinn Chen, Hepatitis Research Center, National Taiwan University College of Medicine and Hospital, Taipei Taiwan