OBJECTIVES: To assess the clinical effectiveness of combined therapy with interferon (pegylated or non-pegylated) and ribavirin versus interferon alone for the treatment of chronic HCV in adult patients. METHODS: We used standard HTA methods as PICOs, comparative analysis, descriptive epidemiology to evaluate a clinical effectiveness of the anti HCV treatment in several respectable trials. Studies eligible for inclusion were systematic reviews of randomized controlled trials (RCTs), RCTs, HTA reports, economic evaluations, high quality primary studies (preferably RCTs). Preference was given to references published in the English or Russian languages and preferably published within the past 10 years (2002 forward). RESULTS: All subgroups of included trials consisted of 13,331 patients with chronic hepatitis C without HIV infection or liver transplantation with diagnosed on the presence of serum hepatitis C virus RNA plus elevated serum transaminase activity for more than 6 months or chronic hepatitis documented by liver biopsy. All of the included studies detected the clinical efficacy of combined therapy of IFN + RBV. According to trials, patients with non-1 genotype had higher virological response rates than patients with genotype 1. Genotype 1 patients had significantly higher SVR rates when treated for 48 weeks compared with 24 weeks. PEG and four IFN trials reported alanine aminotransferase (ALT) response rates after treatment. Sustained biochemical response was greater for IFN + RBV compared with IFN monotherapy or IFN with placebo, reaching significance in two trials and borderline significance in one trial. CONCLUSIONS: The clinical effectiveness of the combined therapy with ribavirin and interferon is convincing. However, using the ribavirin in combination with interferon (pegylated or non-pegylated) can not be final, owing to the many adverse effects. Assessment of the recovery of patients by the sustained virologic response should not be so pragmatic, because it is only a change of the "surrogate" criterias.