***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: Three trials involving 126 patients were included, with complete data available for 93 patients. The participants were heterogeneous, none of the three studies examined exactly the same interventions or measured the same outcomes. Only two trials reported mortality data and the summary relative risk for mortality of the intervention was 5.4 (95% CI 0.27 to 107.09). One trial reported increased coagulation times in the transfused group, and reported these patients to have increased rates of rebleeding. None of the studies reported adverse events directly related to RBC transfusion. Methodological deficiencies, including allocation concealment, generation of random sequences and blinding, simply compound the uncertainty surrounding analysis. None of the studies were appropriately powered and in the largest study fewer than half the participants were included in the final analysis. One RCT of restrictive versus liberal RBC transfusion aims to recruit 860 patients but has yet to be completed. There were more deaths and more rebleeding in the transfusion arms of the combined studies, but the small numbers of participants and large volume of missing data limit the significance of the findings. The studies in this review do not provide useful data regarding outcomes following red blood cell transfusion for acute upper gastrointestinal haemorrhage. They appear to exclude large survival benefit. Large, well-concealed RCTs of sufficient power are urgently needed.
Output:

This update found no new eligible trials. The original review found three trials investigating the effects of red blood cell transfusion in patients with upper gastrointestinal tract bleeding. There were more deaths recorded in the transfusion arm of the combined studies compared to the control arm. It is by no means clear that transfusion is a surrogate marker for more severe haemorrhage. The deaths were too few and the trials too disparate to draw any firm conclusions regarding the effects of transfusion on mortality. We can only recommend that further, larger studies are done.