***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 were eligible. All had high risk of bias and reporting was inconsistent. Hepatitis B vaccine did not show a clear effect on the risk of developing HBsAg (RR 0.96, 95% CI 0.89 to 1.03, 4 trials, 1230 participants) and anti-HBc (RR 0.81, 95% CI 0.61 to 1.07; 4 trials, 1230 participants, random-effects) when data were analysed using intention-to-treat analysis assuming an unfavourable event for missing data. Analysis based on data of available participants showed reduced risk of developing HBsAg (RR 0.12, 95% CI 0.03 to 0.44, 4 trials, 576 participants) and anti-HBc (RR 0.36, 95% CI 0.17 to 0.76, 4 trials, 576 participants, random-effects). Intention-to-treat analysis assuming favourable outcome for missing data showed similar reduction in risk. Hepatitis B vaccination had an unclear effect on the risk of lacking protective antibody levels (RR 0.57, 95% CI 0.26 to 1.27, 3 trials, 1210 participants, random-effects). Development of adverse events was sparsely reported. In people not previously exposed to hepatitis B, vaccination has unclear effect on the risk of developing infection, as compared to no vaccination. The risk of lacking protective antibody levels as well as serious and non-serious adverse events appear comparable among recipients and non-recipients of hepatitis B vaccine.
Output:

Twelve randomised clinical trials fulfilled the inclusion criteria of this review. Primary analysis of the data based on criteria described beforehand (intention-to-treat model assigning unfavourable outcome for missing data) showed that hepatitis B vaccination has an unclear effect on the risk of developing hepatitis B infection. Analysis of data of available participants in the various trials showed that as compared to not vaccinating, hepatitis B vaccination reduces the risk of developing hepatitis B infection; by 88% for hepatitis B surface antigen marker and 62% for anti-core antibody marker. One should note, that these findings are based on only four randomised clinical trials of poor methodological quality involving 1230 participants. When compared with other vaccines or placebo, hepatitis B vaccination results in comparable risk of developing adverse events. This includes serious adverse events such as admission to hospital and convulsions, as well as less serious events such as fever, local redness, and pain. This shows that the risk of developing these adverse events is not more than with other vaccinations. There was not enough data to draw definite conclusions on the effect of hepatitis B vaccination on compliance and cost-effectiveness.