***TASK***
the task is to simplify the input abstract of a biomedical literature

***INPUT***
the input is the abstract of a biomedical literature

***OUTPUT***
the output is the simplified abstract for the input abstract of a biomedical literature

***DOCUMENTATION***

***EXAMPLES***

Input: A total of 501 liver transplant recipients undergoing liver transplantation for chronic HCV infection were randomised in 12 trials to various experimental interventions and control interventions. The proportion of genotype I varied between 49% and 100% in the seven trials that reported the genotype. Only one or two trials were included under each comparison. All the trials were of high risk of bias. Ten trials including 441 liver transplant recipients provided data for this review. There were no significant differences in the 90-day mortality (1 trial; 81 participants; 5/35 (adjusted proportion: 14.2%) in interferon group versus 5/46 (10.9%) in control group; RR 1.31; 95% CI 0.41 to 4.19); mortality at maximal follow-up (2 trials; 105 participants; 7/47 (adjusted proportion: 14.8%) in interferon group versus 10/58 (17.2%) in control group; RR 0.86; 95% CI 0.36 to 2.08); long-term mortality (1 trial; 81 participants; HR 0.45; 95% CI 0.13 to 1.56); mortality at maximal follow-up (1 trial; 54 participants; 1/26 (3.9%) in pegylated interferon group versus 2/28 (7.1%) in control group; RR 0.54; 95% CI 0.05 to 5.59); 90-day mortality (1 trial; 115 participants; 5/55 (9.1%) in pegylated interferon plus ribavirin group versus 3/60 (5.0%) in control group; RR 1.82; 95% 0.46 to 7.25); 90-day mortality (3 trials; 53 participants; 3/37 (adjusted proportion: 4.3%) in HCV antibody group versus 1/16 (6.3%) in placebo group; RR 0.69; 95% CI 0.15 to 3.11); or 90-day mortality (2 trials; 31 participants; 2/14 (adjusted proportion: 16.2%) in HCV antibody high-dose group versus 1/17 (5.9%) in HCV antibody low-dose group; RR 2.75; 95% CI; 0.30 to 25.35). There were no significant differences in the retransplantation at maximal follow-up (2 trials; 105 participants; 2/47 (adjusted proportion: 4.0%) in interferon group versus 2/58 (3.4%) in control group; RR 1.17; 95% CI 0.22 to 6.2); 90-day retransplantation (1 trial; 18 participants; 1/12 (8.3%) in HCV antibody group versus 0/6 (0%) in control group; RR 1.71; 95% CI 0.09 to 32.93); or 90-day retransplantation (1 trial; 12 participants; 1/6 (17.7%) in HCV antibody high-dose group versus 0/6 (0%) in HCV antibody low-dose group; RR 3.00; 95% CI 0.15 to 61.74). There were no significant differences in serious adverse events, graft rejection, worsening of fibrosis, or HCV recurrence between intervention and control groups in any of the comparisons that reported these outcomes. None of the trials reported quality of life, liver decompensation, intensive therapy unit stay, or hospital stay. Life-threatening adverse events were not reported in either group in any of the comparisons. There is currently no evidence to recommend prophylactic antiviral treatment to prevent recurrence of HCV infection either in primary liver transplantation or retransplantation. Further randomised clinical trials with adequate trial methodology and adequate duration of follow-up are necessary.
Output:

Ten trials including 441 liver transplant recipients provided data for this review. The patients were randomised to receive different treatments or no treatment in these 10 trials. We found two other trials, but data were not provided. There were no significant differences in the proportion of patients who died or required retransplantation within 90 days or at maximal follow-up between the different treatment groups for any of the comparisons. There were no significant differences in serious complications, graft rejection, microscopic features of liver damage, or evidence of chronic hepatitis C recurrence between the different treatment groups or no treatment in any of the comparisons that reported these outcomes. None of the trials reported quality of life, liver failure, intensive therapy unit stay, or hospital stay. Life-threatening adverse events were not reported in any of the comparisons. There is currently no evidence to recommend preventive antiviral treatment to prevent recurrence of chronic HCV infection either in primary liver transplantation or retransplantation. All the trials were at high risk of systematic errors (ie, there was potential to arrive at wrong conclusions because of the way the trial was conducted) and random errors (there was potential to arrive at the wrong conclusions because of the play of chance). Overall, the quality of evidence was very low. Further randomised clinical trials with low risk of random errors and systematic errors are necessary to assess the long-term survival benefits for various treatment options in these patients. Such trials should include patient-oriented outcomes such as mortality, graft failure, graft rejections, and quality of life.