SVR12 in patients according to fibrosis stage. SVR12 was defined as undetectable HCV RNA 12 weeks after completion of treatment. P values were determined using the chi-squared test. BID, twice daily; HCV, hepatitis C virus; NR, no ribavirin; SVR12, sustained virologic response 12 weeks after completion of treatment; TID, three times daily. Numbers at the bottom of bars are number of patients with SVR12/total number of patients. Numbers above the bars are percentages.