***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: Nine trials were identified in the searches and five trials, with a total of 547 participants, met the inclusion criteria. Only one trial reported incidence of pneumococcal infection, and this demonstrated that the polysaccharide pneumococcal vaccine used (PPV14) failed to reduce significantly the risk of infection in children under three years of age, but was associated with only minor adverse events. Three trials of conjugate pneumococcal vaccines found that antibody responses were increased compared to control groups, including those in infants, although clinical outcomes were not measured in these trials. Previous trials have shown that conjugate pneumococcal vaccines are safe and effective in normal healthy individuals, including those under the age of two years. The controlled trials included in this review have demonstrated immunogenicity (the ability to induce the body's immune response, without which there is no protection) of these vaccines, and observational studies in people with sickle cell disease support these findings. We therefore recommend that conjugate pneumococcal vaccines are used in people with sickle cell disease. Randomised trials in people with sickle cell disease will be needed to determine the optimal vaccination regimen when further, potentially more effective vaccines become available. Such trials should measure clinical outcomes of effectiveness. The trials included in this review were published between 1983 and 2003. We have not identified any further relevant trials up to December 2011. We therefore do not plan to update this review until new trials are published.
Output:

We searched for trials which compared a polysaccharide or conjugate pneumococcal vaccine schedule with a different schedule or no vaccination in people with sickle cell disease. The review includes five trials with a total of 547 participants. One trial showed that the polysaccharide vaccine did not reduce the risk of infection very much in children younger than three years old, but it was linked with only minor adverse events. Three trials of conjugate vaccines showed increased antibody responses compared to control groups in people of all ages, although clinical outcomes were not measured in these trials. This review did not show if the vaccines prevent infection or decrease death rates. We recommend that conjugate pneumococcal vaccines are used in people with sickle cell disease. Randomised trials will be needed to determine the best vaccination schedule when further, potentially more effective vaccines become available. Such trials should measure clinical outcomes of effectiveness.