***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: Twelve trials on artificial or bioartificial support systems versus standard medical therapy (483 patients) and two trials comparing different artificial support systems (105 patients) were included. Most trials had unclear methodological quality. Compared to standard medical therapy, support systems had no significant effect on mortality (RR 0.86; 95% CI 0.65 to 1.12) or bridging to liver transplantation (RR 0.87; 95% CI 0.73 to 1.05), but a significant beneficial effect on hepatic encephalopathy (RR 0.67; 95% CI 0.52 to 0.86). Meta-regression indicated that the effect of support systems depended on the type of liver failure (P = 0.03). In subgroup analyses, artificial support systems appeared to reduce mortality by 33% in acute-on-chronic liver failure (RR 0.67; 95% CI 0.51 to 0.90), but not in acute liver failure (RR 0.95; 95% CI 0.71 to 1.29). Two trials comparing artificial support systems showed significant mortality reductions with intermittent versus continuous haemofiltration (RR 0.58; 95% CI 0.36 to 0.94) and no significant difference between five versus ten hours of charcoal haemoperfusion (RR 1.03; 95% CI 0.65 to 1.62). The incidence of adverse events was inconsistently reported. This Review indicates that artificial support systems may reduce mortality in acute-on-chronic liver failure. Artificial and bioartificial support systems did not appear to affect mortality in acute liver failure. However, considering the strength of the evidence additional randomised clinical trials are needed before any support system can be recommended for routine use.
Output:

Evidence from twelve small randomised trials were combined. Most trials had unclear methodologic quality. Overall, support systems did not appear to affect mortality or bridging to transplantation, but had a beneficial effect on hepatic encephalopathy. The risk of adverse events could not be established. Further evidence is needed before support systems can be recommended for routine use.