rule stopping rule PMID: 17591081-BACKGROUND/AIMS: To investigate the viral kinetics of Chinese CHC patients received pegylated interferon plus ribavirin and examine the impact of HCV genotypes and severity of liver disease. METHODOLOGY: 65 treatment-naove CHC patients who finished a 24-week therapy with peginterferon (alpha-2b (1.5 mcg/kg/week) plus ribavirin (1000-1200 mg /day) and 24 weeks of follow-up were enrolled. Hepatic fibrosis was graded by the METAVIR scoring system. Serum quantitative HCV RNA was determined by Versant HCV RNA 3.0 assay (Bayer Inc.). RESULTS: Genotype non-1 patients responded quickly and a higher percentage of them achieved undetectable HCV RNA (< 615 IU/mL) at week 4 compared with genotype 1 patients (93% vs. 69%, p = 0.018). Degree of hepatic fibrosis significantly affected end-of-treatment and sustained response (SVR). For patients who did not achieve early virological response (EVR), the negative predictive value for SVR was 100%. In genotype 1 patients, undetectable HCV RNA by week 4 was a good marker to predict treatment response, with a positive predictive value of 84% and a negative predictive value of 82%. CONCLUSIONS: EVR can be applied to Chinese patients as an early stopping rule. A 24-week duration of pegylated IFN/ribavirin might be adequate for genotype 1 patients who rapidly responded to therapy. PRS PRS a stopping rule (criterion) is_a *rule* which causes a *stopping process* to happen stopping rule pending final vetting