Study designs of evaluations included in the review
Clinical trials were eligible for inclusion. In the included studies, the duration of follow-up ranged from 5.25 to 84 months after the start of IFN treatment.
Specific interventions included in the review
Studies of IFN either alone or in combination with ribavirin were eligible for inclusion. IFN was always administered subcutaneously. The patients also received a variety of immunosuppressive drugs.
Participants included in the review
It was clear that studies of renal transplant patients with hepatitis C were to be included. Studies of previously treated patients, nonresponders or relapsers were excluded, as were studies of patients on maintenance dialysis. The mean age of patients in the included studies ranged from 36 to 48 years, and most were men (range: 54 to 100%). Half of the included studies were conducted in Asian countries (Japan, Hong Kong and Taiwan). In all but one study, in which patients had acute de novo hepatitis, the patients had chronic hepatitis C.
Outcomes assessed in the review
Studies that reported adequate data about the sustained virological response (SVR) and/or drop-out rate were eligible for inclusion. SVR was defined as the disappearance of HCV viraemia by polymerase chain reaction at least 6 months after completion of treatment. Viral response had to be measured using the polymerase chain reaction method. The review also assessed sustained biochemical response, which was defined as the normalisation of alanine aminotransferase levels at least 6 months after treatment completion.
How were decisions on the relevance of primary studies made?
It appears that more than one reviewer selected the studies and reached agreement about inclusions.